ABSTRACT
The effects of 8-week ethanol intake (3% v/v in drinking water) on the sexual activity of male rats were investigated during three experimental sessions with 15-day intersession intervals. Chronic ethanol consumption did not significantly influence any copulatory parameter during the three experimental sessions. The evaluation of ultrasonic emission during sexual behavior showed that rats treated with ethanol exhibited a significant increase of the postejaculatory vocalization length during the third test session. These results indicate that the chronic intake of low doses of ethanol, which does not induce either tolerance or dependence, only slightly affects the motivational state of male rats during sexual activity.
Subject(s)
Ethanol/administration & dosage , Sexual Behavior, Animal/drug effects , Animals , Copulation/drug effects , Ethanol/pharmacology , Kinetics , Male , Rats , Rats, Wistar , Ultrasonics , Vocalization, Animal/drug effectsABSTRACT
Studies were carried out in the rat to investigate whether glutamic acid is involved in the regulation of vasopressin (VP) release. For this purpose plasma VP levels were measured in rats treated with the glutamate agonist N-methyl-D-aspartate (NMDA). In our experimental conditions NMDA induced dose-related increases in plasma VP levels in normohydrated rats. The effect of NMDA were prevented by 3[(+)-2 carboxy-piperazine-4-yl]propyl-1-phosphonic acid (CPP), a selective and competitive antagonist of NMDA receptors. These data show that glutamate may contribute to the physiological release of VP from the neurohypophysis.
Subject(s)
N-Methylaspartate/pharmacology , Receptors, N-Methyl-D-Aspartate/drug effects , Vasopressins/blood , Vasopressins/metabolism , Animals , Blood-Brain Barrier/drug effects , Hypothalamus/drug effects , Male , Plasma/drug effects , Rats , Rats, WistarABSTRACT
Adult male rats subjected to a two-way avoidance task emitted ultrasonic vocalizations (20-30 kHz) both during the presentation of the conditioned stimulus and the intertrial interval. The rate of ultrasonic calling decreased during the 75-trial session indicating that acquisition of the conditioned avoidance response (CAR) was inversely correlated with the rate of vocalization. The rate of acquisition of the CAR was most rapid in those rats that did not emit any vocalization during learning. These data suggest that ultrasonic calling during stressful situations may be sensitive indicator of underlying emotional states that interfere with the acquisition of a complex task.
