The GABAB antagonist CGP 35348 inhibits the effects of baclofen on sexual behavior and motor coordination

Abstract

The intraperitoneal injection of 100 mg/kg of CGP 35348 completely blocked the effects of 2.5 mg/kg of (R)-baclofen on sexual behavior and motor coordination in male rats. Doses of 50 and 25 mg/kg partially blocked the effects of (R)-baclofen on sexual behavior but not those on motor coordination. The antagonist itself had no effect on these behaviors. These observations confirm previous data suggesting that the inhibitory effect of (R)-baclofen on sexual behavior is not only a consequence of motor deficiencies and indicates that this effect is due to an action at GABAB receptors. The lack of effect of CGP 35348 on sexual behavior when the drug was administered alone may suggest that GABAB receptors are not important for the physiological control of sexual behavior.