In this study, we investigated whether risperidone, a serotonin-S2A (5-HT2A)/dopamine-D2 (D2)-receptor antagonist, inhibits phencyclidine (PCP)-induced stereotyped behaviors in comparison with haloperidol and ritanserin. Moreover, we also attempted to investigate the effects of these antipsychotics on the contents of dopamine, serotonin (5-HT) and their metabolites in rat striatum and frontal c...

In order to investigate whether early malnutrition causes lasting changes in the reactivity to anxiolytic drugs, rat dams lactation (21 days) and pops after weaning until the 49 th day of life were fed on 8% casein diet (M rats), while their well-nourished controls received 25% casein (W rats), from day 50 on all animals ate the same balanced diet. Experiments started on the 91 st day. Rats dep...

INTRODUCTION: 5-HT2A receptors are of significant clinical interest because of their potential involvement in mediating a variety of physiological functions, including platelet aggregation, thrombus formation, coronary artery spasm, vascular smooth muscle contraction, appetite, sleep, cognition, perception, mood, and other central nervous system functions. Different antagonists such as ketanser...

Plasma thyrotropin (TSH) levels have been previously shown to be associated with the internal sleep structure determined by conventional scoring of sleep stages. This temporal relationship was re-evaluated using spectral analysis of the sleep electroencephalogram (EEG). Eight healthy male subjects underwent two randomized night studies after having received either placebo or 5 mg ritanserin, a ...

A new, non-invasive method for measuring reserpine-induced tremor in rodents is described here. The test procedure is based on the piezo-electric principle and was evaluated using the tremorogenic compound reserpine and the stereotypies-inducing drug apomorphine. Whereas for reserpine an orderly and dose-related increase in activity was observed, no such effect was detected with apomorphine. In...

Upper airway obstruction (UAO) can lead to abnormal growth hormone (GH) homeostasis and growth retardation but the mechanisms are unclear. We explored the effect of UAO on hypothalamic GH-releasing hormone (GHRH), which has a role in both sleep and GH regulation. The tracheae of 22-day-old rats were narrowed; UAO and sham-operated animals were sacrificed 16 days post-surgery. To stimulate slow-...

N-methyl-D-aspartate (NMDA) receptor antagonists such as phencyclidine (PCP) and ketamine can evoke psychotic symptoms in normal individuals and schizophrenic patients. Here, we have examined the effects of PCP (5 mg/kg) and ketamine (25 mg/kg) on the efflux of serotonin (5-HT) in the medial prefrontal cortex (mPFC) and their possible blockade by the antipsychotics, clozapine, olanzapine and ha...