Psilocybin, a tryptamine alkaloid found naturally in numerous Psilocybe mushroom species, is currently being investigated for its therapeutic potential in treating several neurobehavioral and psychiatric diseases. Our previous data showed that the 5-HT2B receptor (5-HT2BR) immobility and increases in climbing behavior in the forced swim test (FST), revealing that psilocybin's predictive...
BACKGROUND: Major depressive disorder is one of the most debilitating psychiatric disorders worldwide. First-line treatments such as selective serotonin reuptake inhibitors have significant limitations, including delayed onset of therapeutic effects and treatment resistance in about 30% of patients. Increasing evidence suggests that acute administration of serotonergic psychedelics, such as...
RATIONALE: Social withdrawal in the sub-chronic phencyclidine (PCP) rat model—a behavioral correlate of schizophrenia’s negative symptoms—is well characterized, yet the psychological mechanisms underlying this deficit remain unclear. OBJECTIVES: Despite the complexity of social behavior, assessments often rely on a single metric (e.g., total interaction time) that has limited explanatory power,...
Social withdrawal is a core negative symptom of schizophrenia and remains poorly understood at the molecular level. Dysregulation of the endocannabinoid system has been implicated in social behavior, yet its downstream signaling mechanisms are not fully characterized. In this context, this study examined the effects of the fatty acid amide hydrolase (FAAH) inhibitor, URB597, on CREB expression...
Psilocybin, a naturally occurring psychedelic compound in magic mushrooms, shows promise as a novel intervention with a single administration inducing rapid and long-lasting antidepressant effects. However, there are limited studies on the optimal dosing required for the beneficial effects of psilocybin given its side effects. To address this gap, we investigated in Wistar rats whether a single...
Social withdrawal in the sub-chronic phencyclidine (PCP) rat model, a behavioral correlate of the negative symptoms of schizophrenia, results from deficits in brain endocannabinoid transmission. As cannabis intake has been shown to affect negatively the course and expression of psychosis, we tested whether the beneficial effects of endocannabinoid-mediated CB1 activation on social withdrawal in...
Social withdrawal should not be considered a direct measure of the negative symptoms of schizophrenia as it may result not only from asociality (primary negative symptom) but also from other altered processes such as anxiety. To understand the contribution of these two factors to social deficit, we investigated whether the social withdrawal observed in the subchronic phencyclidine (PCP) rat...
The fatty acid amide hydrolase inhibitor, URB597, an endocannabinoid enhancing drug, reverses social withdrawal in the sub-chronic PCP rat model of schizophrenia, but reduces social interaction (SI) in controls. To identify the anatomical substrates associated with PCP-induced social withdrawal and the contrasting effects of URB597 on SI in PCP- versus saline-treated rats, we analyzed...
Previous studies have shown that social withdrawal in the phencyclidine (PCP) rat model of schizophrenia results from deficient endocannabinoid-induced activation of CB1 receptors. To understand the underlying cognitive mechanisms of the social deficit in PCP-treated rats, we examined the impact of pharmacological manipulation of the endocannabinoid system on sociability (i.e. social approach)...
Sub-chronic administration of PCP produces a social interaction deficit that is reversed by URB597, an inhibitor of the catabolic enzyme of the endocannabinoid anandamide. Since increased anxiety may contribute to social withdrawal and URB597 has been shown to have an anxiolytic action, we studied whether this drug affected saline- and PCP-treated rats' performance in the Elevated-Plus-Maze...