Effects of progesterone treatment during adulthood on consummatory and motivational aspects of sexual behavior in male rats
In males of a variety of species, administration of progesterone during adulthood has been shown to decrease the expression of consummatory sexual behaviors and androgen receptors. However, it remains to be determined if the progesterone-induced decrease in androgen-receptor signaling and consummatory sexual behaviors correspond with less of a preference for a sexually receptive female relative to another male, a behavioral phenotype indicative of sexual motivation. Consistent with the effects of progesterone reported in males of other species, progesterone-treated rats, relative to vehicle-treated rats, exhibited fewer in...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Short Report Source Type: research

Differential effects of d-amphetamine and atomoxetine on risk-based decision making of Lewis and Fischer 344 rats
In this study, we evaluated dose-dependent effects of d-amphetamine and atomoxetine on probabilistic discounting of Lewis and F344. Male Lewis and F344 chose between one food pellet delivered 100% of the time and three food pellets delivered following decreasing probabilities of delivery (i.e. 100%, 66.7%, 33.3%, 16.5%, and 8.25%). Saline, d-amphetamine (0.1–1.8 mg/kg), and atomoxetine (0.1–7.8 mg/kg) were tested acutely. Lewis and F344 did not differ in choice at baseline. d-Amphetamine increased risky choice for both rat strains at low-to-moderate doses, although it did so at a lower dose (0.1 and 0.3 mg/kg) ...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

The effects of Engelhardtia chrysolepis Hance on long-term memory and potential dopamine involvement in mice
In this study, we investigated the effects of ECH and ASB on long-term memory in mice using a battery of behavioral tests. Acute ECH treatments dose-dependently facilitated nonspatial, but not spatial, memory. ECH treatments also upregulated expression of tyrosine hydroxylase, the enzyme mediating catecholamine synthesis, in neuroblastoma cell culture. Acute ASB treatments similarly improved nonspatial memory, whereas chronic ASB treatments improved both nonspatial and spatial memory. In accordance with such behavioral effects, the increased ratio of tissue concentrations of dopamine metabolites over dopamine in striatal r...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Effect of amphetamine dose on wheel-running functioning as reinforcement or operant behavior on a multiple schedule of reinforcement
This study addressed this question using a multiple schedule of reinforcement in which wheel running served as reinforcement for lever pressing in one component and as operant behavior for sucrose reinforcement in the other component. Seven female Long–Evans rats were exposed to a multiple schedule in which pressing a lever on a variable ratio 10 schedule produced the opportunity to run for 15 revolutions in one component and running 15 revolutions produced a drop of 15% sucrose solution in the other component. Doses of 0.5, 1.0, and 2.0 mg/kg D-amphetamine were administered by intraperitoneal injection 20 min prior ...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

PT-31, a putative α2-adrenoceptor agonist, is effective in schizophrenia cognitive symptoms in mice
In conclusion, PT-31 displayed a preclinical pharmacology predictive of neuroprotective effects and efficacy in relieving schizophrenia symptoms, without inducing motor side effects, suggesting that it could represent a molecular scaffold for antipsychotic drug development. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Locomotor sensitization in male Sprague-Dawley rats following repeated concurrent treatment with 4-methylmethcathinone and 3,4-methylenedioxymethamphetamine
Recreational abuse of illicit synthetic cathinones is an ongoing public health concern. Recent studies indicate that the methcathinone derivative 4-methylmethcathinone (4-MMC) produces behavioral and neurochemical effects similar to the entactogen 3,4-methylenedioxymethamphetamine (MDMA). Whereas polysubstance abuse is common, most preclinical studies of drug abuse liability only evaluate the effects of single drugs. Utilizing the locomotor sensitization paradigm, the present study assessed the combined locomotor stimulant effects of 4-MMC and MDMA for induction of sensitization following repeated administration and for ex...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Repeated administration of synthetic cathinone 3,4-methylenedioxypyrovalerone persistently increases impulsive choice in rats
This study examined if MDPV administration alters impulsive choice measured by delay discounting in rats. Three groups of rats were tested in daily delay discounting sessions to determine the effects of acute cocaine (1.0–30.0 mg/kg), MDPV (0.1–3.0 mg/kg), or saline on mean adjusted delay (MAD). Dose-dependent decreases in MAD were elicited only by acute MDPV, which also suppressed operant responding at the highest dose. Next, rats received post-session injections (30.0 mg/kg cocaine, 3.0 mg/kg MDPV, or saline) every other day for a total of 10 injections. MAD increased during saline treatment, did not change d...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

A single administration of Neurotropin reduced the elongated immobility time in the forced swimming test of rats exposed to repeated cold stress
Many people suffer from a major depressive disorder, and chronic pain conditions are often associated with depressive symptoms. Neurotropin, an extract from the inflamed skin of rabbits inoculated with vaccinia virus, has been used for pain relief. Decrease of brain-derived neurotrophic factor (BDNF) in the brain is one of the proposed mechanisms for the major depressive disorders, and Neurotropin has been reported to restore the decreased BDNF in the hippocampus. In this experiment, we examined whether Neurotropin had an antidepressant-like effect in a model of fibromyalgia and whether BDNF in the brain was altered after ...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Sex and housing conditions modify the effects of adolescent caffeine exposure on anxiety-like and depressive-like behavior in the rat
Previously observed antidepressant-like effects of caffeine in adolescent rats have been shown in individually housed (IH) rats. Because IH presents a social stressor that may create depressant-like effects in control animals, this study sought to compare the effects of chronic caffeine in IH and pair-housed (PH) adolescent male and female rats. Housing conditions began on postnatal day 24 (P24) and half of the rats were provided caffeine (0.25 g/l) in their drinking water beginning on P28. Open-field behavior was assessed on P42, a light/dark test was conducted on P43, and a forced swim test was conducted on P44–P45...
Source: Behavioural Pharmacology - September 14, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Neuropathic insult increases the responsiveness to acetic acid in mice
Chronic neuropathic pain is a burden to millions of patients every day. Patients with neuropathic pain will also experience acute pain throughout their everyday lives adding to their nociceptive burden. Using nociceptive models in mice this study aimed to investigate the relationship between acute visceral pain and chronic neuropathic pain in spontaneous and affective behaviors. Neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve of C57BL/6J male mice and examined in assays of acetic acid (AA)-induced stretching or conditioned place aversion to assess nociceptive and aversive behaviors. S...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Short Reports Source Type: research

Clonidine, an α2 adrenergic receptor agonist, disrupts reconsolidation of a cocaine-paired environmental memory
Environmental cues can elicit robust cocaine reward memories, contributing to relapse to cocaine abuse. Memories can be manipulated pharmacologically by interfering with reconsolidation after reactivation. Clonidine, an α2 noradrenergic receptor agonist, was tested for its ability to block reconsolidation of cocaine environmental-paired memory. Male Sprague-Dawley rats completed an 8-day cocaine place conditioning procedure to establish a cocaine place preference. Cocaine memory was reactivated by exposure to the cocaine-paired environment in a drug-free state, followed immediately by administration of clonidine (10 ...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Short Reports Source Type: research

Discriminative stimulus properties of the typical antipsychotic haloperidol compared to other antipsychotic drugs in C57BL/6 mice
This study used a drug discrimination assay to allow a direct comparison between the subjective effects of HAL and other APDs. Eleven C57BL/6 mice were trained to discriminate 0.05 mg/kg HAL from the vehicle in a two-lever drug discrimination task. The HAL generalization curve (0.001563–0.2 mg/kg) yielded an ED50=0.0024 mg/kg (95% confidence interval: 0.0012–0.0048 mg/kg). The typical APD chlorpromazine produced full substitution at 4.0 mg/kg with 82.7% drug-lever responding (%DLR) with significant rate suppression and partial substitution (73.9% DLR) at 1.0 mg/kg with no rate suppression. The atypical APD cloz...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Functional lateralization in the prefrontal cortex of dopaminergic modulation of memory consolidation
There is increasing evidence of functional lateralization within the rat brain. Here, we have examined the lateralization of dopamine (DA) function in the medial prefrontal cortex (PFC) in relation to memory consolidation in the novel object recognition test (NOR). Male Wistar rats received single bilateral or unilateral injections into prelimbic-PFC of agonists (SKF81297; 0.2 µg, quinpirole; 1 µg, SB277,011; 0.5 µg) and antagonists (SCH23390; 3 µg, L-741,626; 1 µg, 7-OH-DPAT; 3 µg) at DA D1, D2, or D3 receptors, immediately following the exposure trial in the NOR, and were tested either...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Optogenetic inhibition of the medial prefrontal cortex reduces methamphetamine-primed reinstatement in male and female rats
Preclinical findings suggest sex-differences exist in drug-seeking behavior following methamphetamine (METH) self-administration. The medial prefrontal cortex (mPFC), is thought to contribute to the reinstatement of drug-seeking in males. Glutamatergic neurons project from the prelimbic portion of the mPFC to various brain regions modulating activity including the nucleus accumbens; thus the prelimbic region of the mPFC is thought to contribute to drug-seeking behaviors. Although studied in males, little research has investigated the role of the mPFC in females. The purpose of this study was to investigate if the prelimbic...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Effects of N-ethylpentylone on locomotor activity and anxiety-like behavior in rats
In this study, locomotor stimulation and sensitization, as well as anxiety-like behavior induced by NEP were studied in Sprague-Dawley rats, using the open field and elevated plus maze respectively. Rats were administered NEP (5, 20 or 50 mg/kg, intraperitoneal), with saline as the negative control and methamphetamine (5 mg/kg) as a positive control. Acute administration of NEP at all the doses tested significantly promoted locomotor activity, presenting an inverted U-shaped dose-effect curve. The highest activity was observed at the 20 mg/kg dose group, with the average distance traveled 18 times higher than the saline gr...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Changes in behavioral and neuronal parameters by alcohol, cigarette, or their combined use in rats
Few studies have explored the effects of the combined use of alcohol and cigarette in humans, despite its prevalence. Here we evaluated the effect of isolated and combined use on behaviors and neuronal parameters in rats. Male adult rats were divided into alcohol (AL, 2 g/kg, by oral gavage), cigarette smoke (TB, six cigarettes, by inhalation), combined use (ALTB), or control (CT, water by oral gavage and environmental air) groups, treated twice a day (09.00 and 14.00 h). After 4 weeks, the rats were tested in the open field for behavioral analysis and euthanized for brain volume estimation and counting of neurons in the h...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

The muscarinic agonist pilocarpine modifies cocaine-reinforced and food-reinforced responding in rats: comparison with the cholinesterase inhibitor tacrine
This study evaluated its effects on cocaine-reinforced and food-reinforced behaviors in rats, using the cholinesterase inhibitor tacrine as a comparator. Intraperitoneal pilocarpine or tacrine at doses of 1.0 mg/kg or more attenuated self-administration of low-dose cocaine (0.1 mg/kg injection) but also increased oral movements. Pilocarpine was less potent than tacrine in decreasing responding supported by low or intermediate amounts of liquid food. Combined treatment with pilocarpine and tacrine was more effective than either compound alone in attenuating self-administration of intermediate-dose cocaine. At a low (0.66 mg...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Role of AMPA receptor stimulation and TrkB signaling in the antidepressant-like effect of ketamine co-administered with a group II mGlu receptor antagonist, LY341495, in the forced swim test in rats
Ketamine has been shown to induce a rapid antidepressant effect on patients with depression. In many animal models, both rapid and sustained antidepressant activities were also found in response to an antagonist of group II metabotropic glutamate receptors, LY341495, and its mechanism of action seemed to be similar in many ways to the action of ketamine. It has also been found that LY341495 enhanced the antidepressant-like activity of sub-effective doses of ketamine in rats without inducing adverse effects. Here, we investigated the role of AMPA receptor and TrkB receptor activation in the antidepressant-like effects of ke...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Effects of monoamine uptake inhibitors on pain-related depression of nesting in mice
Pain is a significant public health problem, and assessment of pain-related impairment of behavior is a key clinical indicator and treatment target. Similar to opioids and NSAIDs, dopamine (DA) transporter inhibitors block pain-related depression of intracranial self-stimulation (ICSS) in rats. The primary goal of the present study was to determine if the effects of monoamine uptake inhibitors on pain-related depression of ICSS in rats extend to an assay of pain-related depression of nesting in mice. We hypothesized that the DA transporter-selective uptake inhibitor bupropion would block depression of nesting behavior prod...
Source: Behavioural Pharmacology - August 6, 2019 Category: Drugs & Pharmacology Tags: Research Reports Source Type: research

Effects of the α2/α3-subtype-selective GABAA receptor positive allosteric modulator KRM-II-81 on pain-depressed behavior in rats: comparison with ketorolac and diazepam
This study examined effects of the α2/α3-subtype-selective GABAA receptor positive allosteric modulator KRM-II-81 in an assay of pain-related behavioral depression. Adult, male Sprague-Dawley rats responded for electrical brain stimulation in a frequency-rate intracranial self-stimulation (ICSS) procedure. Intraperitoneal injection of 1.8% lactic acid served as an acute noxious stimulus to depress ICSS. Effects of KRM-II-81 were evaluated in the absence and presence of the acid noxious stimulus. The NSAID ketorolac and the benzodiazepine diazepam were tested as comparators. Neither ketorolac nor KRM-II-81 alter...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Alterations of acoustic features of 50 kHz vocalizations by nicotine and phencyclidine in rats
Ultrasonic vocalizations are widely used to examine affective states in rats, yet relatively few studies explore the acoustic features of vocalizations, especially in relation to drug exposure, and no studies have explored alterations in acoustic features over time. The goal of this study was to examine nicotine- and phencyclidine-induced alterations of bandwidth, duration, and frequency of 50 kHz vocalizations. The minimum and maximum frequency, bandwidth, and duration of calls were examined after 7 days of daily subcutaneous administration of phencyclidine (2.0 mg/kg) and nicotine (0.2 and 0.4 mg/kg) in male Sprague-Dawl...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Parental morphine exposure enhances morphine (but not methamphetamine) preference and increases monoamine oxidase-B level in the nucleus accumbens
Opioid addiction is one of the most crucial issues in the world. Opioid abuse by parents makes children more prone to many psychological disorders such as drug addiction. Therefore, this study was carried out to examine the effect of morphine exposure 10 days before gestation on morphine and methamphetamine preference in male offspring. Adult Wistar rats (male and female) received morphine orally for 21 days and were drug free for 10 days. Thereafter, they were allowed to mate with either a morphine-abstinent or drug-naive rat. The male offspring were tested for morphine and methamphetamine preference with a three-bottle c...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Effects of imidazoline I2 receptor agonists on reserpine-induced hyperalgesia and depressive-like behavior in rats
This study examined the antinociceptive and antidepressant-like effects of imidazoline I2 receptor (I2R) agonists in a reserpine-induced model of fibromyalgia in rats. Rats were treated for 3 days with vehicle or reserpine. The von Frey filament test was used to assess the antinociceptive effects of I2 receptor agonists, and the forced swim test was used to assess the antidepressant-like effects of these drugs. 2-BFI (3.2–10 mg/kg, intraperitoneally), phenyzoline (17.8–56 mg/kg, intraperitoneally), and CR4056 (3.2–10 mg/kg, intraperitoneally) all dose-dependently produced significant ...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Further pharmacological comparison of D-methamphetamine and L-methamphetamine in rats: abuse-related behavioral and physiological indices
This study examined potential abuse-related and adverse physiological effects of D -MA and L -MA alone and in combination in rats, as these effects had not been previously characterized. Potential abuse-related effects were examined in locomotor sensitization and conditioned place preference paradigms. Body temperature was monitored to assess the physiological effects of these drugs or drug combinations. In the locomotor study, D-MA induced locomotor sensitization to both D-MA and L -MA. L -MA induced locomotor sensitization only to D-MA. Responses to a combination of L-MA and D -MA were not differentially affected by L-MA...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Differential cross-tolerance to the effects of nicotinic acetylcholine receptor drugs in C57BL/6J mice following chronic varenicline
This study examined the consequences of daily varenicline treatment on disruptions in operant responding (i.e. rate-decreasing effects) and hypothermia induced by administration of nicotine, epibatidine, cytisine, and cocaine in C57BL/6J mice. Furthermore, mecamylamine was used to assess the involvement of nAChRs in the effects of varenicline. Mice were trained under a fixed ratio 20 of milk reinforcement, and rectal temperatures were measured after 30 min following drug-administration. Varenicline, nicotine, epibatidine, and cytisine produced dose-dependent decreases in response rate and rectal temperature. Chronic...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Normal extinction and reinstatement of morphine-induced conditioned place preference in the GluA1-KO mouse line
Extinction and reinstatement of morphine-induced conditioned place preference were studied in glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-receptor GluA1 subunit-deficient mice (global GluA1-KO mice). In line with previous findings, both acquisition and expression of conditioned place preference to morphine (20 mg/kg, subcutaneously) were fully functional in GluA1 KO mice compared with wild-type littermate controls (GluA1-WT), thus enabling the study of extinction. With a 10-session extinction paradigm, the GluA1 KO mice showed complete extinction similar to that of the GluA1-WT mice. Morphin...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Sexual behaviour of the female rat during late adolescence: effect of chronic cocaine treatment
Sexual behaviour is highly motivated and female rats begin to express it during adolescence. The circuitries implicated in the control of motivated behaviours continue to mature during adolescence and seem more sensitive to the effects of psychostimulants such as cocaine. However, a putative differential effect of this drug on the sexual behaviour of females according to age has not yet been studied. Therefore, we compared the motivational value of a male and the expression of sexual behaviour of late-adolescent and adult female rats after chronic treatment with a vehicle or 15.0 mg/kg cocaine. The strong incentive ...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Functional and molecular changes in the nucleus accumbens of MK-801-sensitized rats
Behavioural sensitization is a putative mechanism in the pathophysiology of drug addiction and neuropsychiatric disorders such as schizophrenia. In rodents, drug-induced behavioural sensitization has been described for several different drug classes. The N-methyl-D-aspartate receptor antagonist MK-801 can inhibit sensitization to other drugs of abuse. However, MK-801 also produces behavioural sensitization to its own hyperlocomotor inducing effects, suggesting that MK-801 sensitization has a distinctive mechanism of action. The aim of this study was to carry out a functional and molecular analysis of the nucleus accumbens ...
Source: Behavioural Pharmacology - July 5, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Select panicogenic drugs and stimuli induce consistent increases in tail skin flushes and decreases in core body temperature
Panic attacks (PAs) are episodes of intense fear or discomfort that are accompanied by a variety of both psychological and somatic symptoms. Panic induction in preclinical models (e.g. rats) has largely been assayed through flight and avoidance behavioral tests and cardiorespiratory activity. Yet, the literature pertaining to PAs shows that thermal sensations (hot flushes/heat sensations and chills) are also a common symptom during PAs in humans. Considering that temperature alterations are objectively measurable in rodents, we hypothesized that select panicogenic drugs and stimuli induce consistent changes in thermoregula...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: SHORT REPORTS Source Type: research

Dietary supplementation with fish oil reverses high fat diet-induced enhanced sensitivity to the behavioral effects of quinpirole
Consuming a high fat diet can lead to many negative health consequences, such as obesity, insulin resistance, and enhanced sensitivity to drugs acting on dopamine systems. It has recently been demonstrated that dietary supplementation with fish oil, which is rich in omega-3 fatty acids, can prevent this high fat diet-induced enhanced sensitivity to dopaminergic drugs from developing. However, it is not known whether fish oil supplementation can reverse this effect once it has already developed. To test the hypothesis that dietary supplementation with fish oil will reverse high fat diet-induced enhanced sensitivity to quinp...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: SHORT REPORTS Source Type: research

The effect of nicotine and nicotine+monoamine oxidase inhibitor on the value of alcohol
Alcohol is the most commonly abused drug in the USA and many people suffer from alcohol use disorder. Many factors are associated with alcohol use disorder, but the causal role of comorbid nicotine use has not been extensively considered. Nicotine has reward-enhancing properties and may increase the value of alcohol. Monoamine oxidase inhibition increases nicotine self-administration and may increase the reward-enhancing effects of nicotine. We assessed the effect of nicotine and nicotine in combination with a commonly used monoamine oxidase inhibitor (tranylcypromine) on the value of alcohol using a progressive ratio sche...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: SHORT REPORTS Source Type: research

Sex differences in the effectiveness of buprenorphine to decrease rates of responding in rhesus monkeys
Sex differences in μ-opioid receptor (MOR) agonist-induced antinociception have been reported in nonhuman primates. The degree to which μ-opioid receptor agonist sex differences in nonhuman primates extend to other behavioral endpoints remains unknown. The present study compared the behavioral effects of three MOR ligands (fentanyl, buprenorphine, and naltrexone) that varied in efficacy to stimulate [35S]-GTPγS binding (from highest to lowest: fentanyl, buprenorphine, and naltrexone) in male and female rhesus monkeys. Male (n=3) and female (n=3) monkeys were trained to respond under a fixed-ratio 10 schedule of...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: SHORT REPORTS Source Type: research

New procognitive enhancers acting at the histamine H3 and AMPA receptors reverse natural forgetting in mice: comparisons with donepezil and memantine in the object recognition task
This study evaluated the procognitive effects of S 38093 (a new inverse agonist of the histaminergic H3 receptor) and S 47445 (a new α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) in 2–3-month-old Swiss mice as compared with donepezil and memantine, two main reference compounds in the treatment of Alzheimer’s disease. The object recognition task allows the study of natural forgetting and is classically used in assessing drug effects on memory. Here, we show that mice exhibit significant object recognition at short (15 min) but not long (24 h) retention intervals separating the famili...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Olfaction in female Wistar rats is influenced by dopaminergic periglomerular neurons after nigral and bulbar lesions
Hyposmia is found in Parkinsonian patients decades before the onset of motor disorders. The same occurs with sleep disorders, especially infuencing rapid eye movement (REM) sleep, which affect a large percentage of people who have Parkinson’s disease. These two disturbances presumably are closely related to a dopaminergic dysfunction. Therefore, we propose that selective lesions, induced by rotenone, of the periglomerular neurons within the olfactory bulb or of the nigrostriatal pathway could result in hyposmia. In addition, we hypothesized that REM sleep deprivation (REMSD) could have potential to generate a synergi...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Punishment and reinforcement by opioid receptor agonists in a choice procedure in rats
Intravenous (i.v.) drug self-administration remains the ‘gold standard’ for assessing abuse potential of drugs. Failure of a drug to maintain self-administration might indicate merely the absence of positive-reinforcing effects but might also indicate presence of aversive effects. Sensitivity to aversive effects is thought to affect the initiation and maintenance of drug use as well as relapse. Choice procedures are used to study positive-reinforcing effects of drugs and to a much lesser extent to study punishing effects of drugs. Experiment 1 compared the μ-opioid receptor agonist remifentanil (0.001–...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Dopamine and serotonin antagonists fail to alter the discriminative stimulus properties of ±methylenedioxymethamphetamine
This study aimed to determine effects of selective dopamine (DA) and serotonin (5HT) antagonists on the discriminative stimulus properties of AMPH (0.5 mg/kg) and MDMA (3.0 mg/kg). Separate groups of rats were trained to discriminate AMPH (0.5 mg/kg) or MDMA (3.0 mg/kg) from saline using a food-reinforced drug-discrimination procedure. Effects of DA (SCH 23390: 0.003–0.03 mg/kg and eticlopride: 0.03–0.3 mg/kg) or 5HT (ritanserin: 1.0–10.0 mg/kg, WAY-100635: 0.3–1.0 mg/kg and GR129375: 1.0–3.0 mg/kg) antagonists on the discriminativ...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Inhibition of experimental visceral pain in rodents by cebranopadol
The aim of this study was to investigate the efficacy of cebranopadol in two rodent models of visceral pain. Cebranopadol is a first-in-class analgesic with agonist activity at the nociceptin/orphanin FQ opioid peptide receptor and classical µ-, δ- and κ-opioid peptide receptors. Colitis was induced in Naval Medical Research Institute mice by intra-rectal infusion of mustard oil. The effects of intravenous cebranopadol pretreatment on spontaneous pain behaviours and referred allodynia and hyperalgesia were assessed. Pancreatitis was induced in Sprague-Dawley rats by intravenous administration of dibutylti...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Chronic clozapine treatment improves the alterations of prepulse inhibition and BDNF mRNA expression in the medial prefrontal cortex that are induced by adolescent social isolation
In this study, male Sprague Dawley rats were randomly assigned to either group-reared or isolation-reared conditions during postnatal days (PNDs) 21–34. During PNDs 46–55, the rats were subjected to chronic clozapine (1.0 mg/kg for 10 days) or saline treatment. On PND 56, all rats underwent behavioral testing and then were sacrificed for biochemical testing. The results indicated that adolescent social isolation induced impairments in prepulse inhibition and reversal learning, and clozapine injection improved the prepulse inhibition disruption but not reversal learning ability. Furthermore, clozapine adm...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Classic animal models of Parkinson’s disease: a historical perspective
The quest to better understand the pathophysiology of Parkinson’s disease (PD) and to find new therapies to provide greater relief to affected patients continues. The use of animal models of PD has been invaluable in the process. Here, we review, through a historical lens, some of the contribution of the 6-hydroxydopamine-lesioned rat and of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned nonhuman primate, in refining our understanding of PD and its treatment-related complications. We examine the mechanisms underlying the toxicity of 6-hydroxydopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and th...
Source: Behavioural Pharmacology - May 14, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLE Source Type: research

Quercetin mitigates anxiety-like behavior and normalizes hypothalamus–pituitary–adrenal axis function in a mouse model of mild traumatic brain injury
The objectives of this study were to determine whether quercetin treatment can attenuate anxiogenic-like behaviors and normalize HPA axis function in mice with mTBI. Animals subjected to mTBI were treated daily with quercetin (50 mg/kg) or diazepam (positive control, 3 mg/kg) for 14 days. Four behavioral tests (open field, plus maze, light-dark box, and zero maze) were used to assess anxiety-related behaviors in mice. To evaluate HPA axis function, adrenocorticotropic hormone and corticosterone were measured in the serum of mice after the anxiety tests. Quercetin treatment was found to significantly reduce an...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Early-life stress influences acute and sensitized responses of adult mice to cocaine by interacting with GABAA α2 receptor expression
Early-life stress (ELS) is known to exert long-term effects on brain function, with resulting deleterious consequences for several aspects of mental health, including the development of addiction to drugs of abuse. One potential mechanism in humans is suggested by findings that ELS interacts with polymorphisms of the GABRA2 gene, encoding α2 subunits of GABAA receptors, to increase the risk for both post-traumatic stress disorder and vulnerability to cocaine addiction. We used a mouse model, in which the amount of material for nest building was reduced during early postnatal life, to study interactions between ELS an...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Early life exposure to cortisol in zebrafish (Danio rerio): similarities and differences in behaviour and physiology between larvae of the AB and TL strains
The objective of this study was therefore to assess the effects of increased levels of cortisol, mimicking thereby maternal stress, on larval physiology and behaviour. We studied the effects in two common zebrafish strains, that is, AB and Tupfel long-fin (TL), to assess strain dependency of effects. Fertilized eggs were exposed to a cortisol-containing medium (1.1 μmol/l) or control medium from 0 to 6 h following fertilization, after which at 5-day following fertilization, larval behaviour and baseline hypothalamus–pituitary–interrenal cells axis functioning were measured. The data confirmed e...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Celecoxib potentiates the antianxiety and anticompulsive-like activity of fluoxetine against chronic unpredictable mild stress in experimental animals
Obsessive–compulsive disorder (OCD) is considered a heterogeneous anxiety disorder that includes compulsions. Celecoxib is considered an adjuvant to fluoxetine in the management of OCD in a clinical study. However, the experimental evidence is yet to be established. Therefore, the antianxiety and anticompulsive-like activity of celecoxib (20 mg/kg, orally) was evaluated in the presence or absence of fluoxetine (20 mg/kg, orally) in mice who were exposed to chronic unpredictable mild stress (CUMS) for 14 consecutive days. Seven-day treatment of celecoxib significantly attenuated the CUMS-induced anxiety ...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Validation of chronic mild stress in the Wistar-Kyoto rat as an animal model of treatment-resistant depression
A recent review proposed four criteria for an animal model of treatment-resistant depression (TRD): a phenotypic resemblance to a risk factor for depression; enhanced response to stress; nonresponse to antidepressant drugs and response to treatments effective in TRD, such as deep brain stimulation (DBS) of the prefrontal cortex or ketamine. Chronic mild stress (CMS) provides a valid model of depression; the Wistar-Kyoto (WKY) rat is considered to be nonresponsive to antidepressant drugs. Here, we applied CMS to WKY rats. WKY and Wistar rats were exposed to CMS, then treated with saline, imipramine, citalopram or venlafaxin...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Influence of aversive stimulation on haloperidol-induced catalepsy in rats
Catalepsy – an immobile state in which individuals fail to change imposed postures – can be induced by haloperidol. In rats, the pattern of haloperidol-induced catalepsy is very similar to that observed in Parkinson’s disease (PD). As some PD symptoms seem to depend on the patient’s emotional state, and as anxiety disorders are common in PD, it is possible that the central mechanisms regulating emotional and cataleptic states interplay. Previously, we showed that haloperidol impaired contextual-induced alarm calls in rats, without affecting footshock-evoked calls. Here, we evaluated the influence of...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

The blockade of corticotropin-releasing factor 1 receptor attenuates anxiety-related symptoms and hypothalamus–pituitary–adrenal axis reactivity in mice with mild traumatic brain injury
Recent studies have shown that mild traumatic brain injury (mTBI) is associated with higher risk for anxiety-related disorders. Dysregulation in the hypothalamus–pituitary–adrenal (HPA) axis following mTBI has been proposed to be involved in the development of neurobehavioral abnormalities; however, the underlying mechanisms are largely unknown. The aim of this study was to determine whether the corticotropin-releasing-factor-1 (CRF-1) receptor is involved in the regulation of anxiety-related symptoms in a mouse model of mTBI. Animals with or without mTBI received intracerebroventricular injections of a CRF-1 r...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Effects of plus-maze experience and chlordiazepoxide on anxiety-like behavior and serotonin neural activity in the dorsal raphe nucleus in rats
The extent to which rats express anxiety-like behavior on the elevated plus-maze (EPM) depends on their previous maze experience. Open-arm avoidance develops in maze-experienced rats, and is often accompanied by a diminished anxiolytic response to benzodiazepines. Regions of the dorsal raphe nucleus (DRN) were examined in male Sprague-Dawley rats using c-Fos and serotonin immunohistochemistry following a single exposure, a second exposure or no exposure to the EPM. We then examined the effect of the benzodiazepine anxiolytic chlordiazepoxide (CDP, 5 mg/kg) on EPM behavior and DRN neural activity. Enhanced open-arm a...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Edaravone prevents memory impairment in an animal model of post-traumatic distress
In conclusion, edaravone ameliorated oxidative stress and cognitive impairment associated with a PTSD model, probably by supporting antioxidant mechanism in the hippocampus. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: RESEARCH REPORTS Source Type: research

Stress and the gut microbiota-brain axis
In conclusion, the influence of stress on gut microbiota and gut microbiota on stress modulation is clear for different stressors, but although the preclinical evidence is so extensive, the clinical evidence is more limited. A better understanding of the mechanism underlying stress modulation through the microbiota may open new avenues for the design of therapeutics that could boost the pursued clinical benefits. These new designs should not only focus on stress but also on stress-related disorders such as anxiety and depression, in both healthy individuals and different populations. (Source: Behavioural Pharmacology)
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research

The ‘Yin’ and the ‘Yang’ of the kynurenine pathway: excitotoxicity and neuroprotection imbalance in stress-induced disorders
The amino-acid tryptophan (TRY) is converted into kynurenine (KYN) and subsequent metabolites by the tryptophan/catabolites (TRY/CAT) pathway (kynurenine pathway). ‘Excito-toxic’ and ‘neuro-protective’ metabolites are produced, which modulate the glutamatergic neurotransmission. The TRY/CAT pathway is activated by hypothalamic–pituitary–adrenal endocrine induction during stress by corticoids hormones, and the excitotoxic branch of the TRY/CAT pathway is activated by proinflammatory cytokines. During stress and major depressive disorders, it is generally accepted that inflammation induces...
Source: Behavioural Pharmacology - March 19, 2019 Category: Drugs & Pharmacology Tags: REVIEW ARTICLES Source Type: research