Ontogenetic Changes in Responsiveness to Benzodiazepine Receptor ligands on Ultrasonic Vocalizations in Rat Pups

摘要

The ontogenetic changes in responsiveness to benzodiazepine receptor ligands on ultrasonic vocalizations in rat pups from the age of day 3 to 12 were evaluated. Rat pups, while separated form their dam and littermates and placed in a cold environment, emit ultrasonic vocalizations. These ultrasonic calls became attenuate dose-dependently in number and power after administration of the anxiolytic diazepam (0.25-1.0 mg/kg, sc), but the inhibitory effect of diazapam at the highest dose was less on day 6 and day 9.