Adolescent Social Stress Increases Anxiety-like Behavior and Alters Synaptic Transmission, Without Influencing Nicotine Responses, in a Sex-Dependent Manner

Publication date: 1 March 2018 Source:Neuroscience, Volume 373 Author(s): Michael J. Caruso, Nicole A. Crowley, Dana E. Reiss, Jasmine I. Caulfield, Bernhard Luscher, Sonia A. Cavigelli, Helen M. Kamens Early-life stress is a risk factor for comorbid anxiety and nicotine use. Because little is known about the factors underlying this comorbidity, we investigated the effects of adolescent stress on anxiety-like behavior and nicotine responses within individual animals. Adolescent male and female C57BL/6J mice were exposed to chronic variable social stress (CVSS; repeated cycles of social isolation + social reorganization) or control conditions from postnatal days (PND) 25–59. Anxiety-like behavior and social avoidance were measured in the elevated plus-maze (PND 61–65) and social approach-avoidance test (Experiment 1: PND 140–144; Experiment 2: 95–97), respectively. Acute nicotine-induced locomotor, hypothermic, corticosterone responses, (Experiment 1: PND 56–59; Experiment 2: PND 65–70) and voluntary oral nicotine consumption (Experiment 1: PND 116–135; Experiment 2: 73–92) were also examined. Finally, we assessed prefrontal cortex (PFC) and nucleus accumbens (NAC) synaptic transmission (PND 64–80); brain regions that are implicated in anxiety and addiction. Mice exposed to adolescent CVSS displayed increased anxiety-like behavior relative to controls. Further, CVSS altered synaptic excitability in PFC and NAC neurons in a sex-specific manner. Fo...
Source: Neuroscience - Category: Neuroscience Source Type: research