Distinct changes in chronic pain sensitivity and oxytocin receptor expression in a new rat model (Wisket) of schizophrenia

Publication date: Available online 16 October 2019Source: Neuroscience LettersAuthor(s): László Banki, Alexandra Büki, Gyongyi Horvath, Gabriella Kekesi, Gyongyi Kis, Ferenc Somogyvári, Gábor Jancsó, Lászlo Vécsei, Endre Varga, Gabor TubolyAbstractClinical studies have shown that schizophrenia is accompanied by hypoalgesia. Accordingly, we have previously reported that a chronic schizophrenia-related rat substrain (Wisket) showed decreased acute heat pain sensitivity. The aim of the present study was to determine the mechanical pain sensitivity and the effects of opioid ligands in a chronic osteoarthritic pain model generated using Wisket rats. Our previous molecular biological studies indicated that the impairment in opioid and cannabinoid receptor functions observed in these animals did not explain their altered pain sensitivity. Therefore, we aimed to investigate another endogenous antinociceptive system, i.e., the oxytocinergic system (which is also implicated in schizophrenia) via the determination the brain-region specific oxytocin receptor mRNA expression in Wisket rats. Osteoarthritis was induced in male adult control Wistar rats without any interventions and in Wisket rats after juvenile social isolation and ketamine treatment. The degree of allodynia and the effects of systemic morphine or intrathecal endomorphin-1 administration were determined. Furthermore, the expression of the oxytocin receptor mRNA was assessed in different brain structures (prefrontal ...
Source: Neuroscience Letters - Category: Neuroscience Source Type: research