Chlordiazepoxide facilitates erections and inhibits seminal emission in rats.

Two experiments have been conducted to clarify the effects of the benzodiazepine chlordiazepoxide (CDP) on the different components of male rat sexual behavior. In the first experiment the effects on penile erectile reflexes (PR) of two doses (10 and 30 mg/kg, IP) of CDP were compared with those of vehicle, no-treatment and baseline pre-test in a repeated measures design. In the second experiment the different components of male sexual behavior - PR, mating behavior and spontaneous seminal emission SSE) - were extensively studied after vehicle, 3 and 30 mg/kg CDP treatments. CDP was found to increase significantly the percentage of rats showing penile reflexes, enhance the number of erections per test and shorten the latency to onset of reflexes. It lowered the percentage of animals displaying seminal emission during the PR test. In the mating behavior test, CDP abolished copulatory (and other) behavior at 30 mg/kg. It decreased the number of animals achieving ejaculation at the subataxic 3 mg/kg dose level. In the SSE 3-day test, CDP significantly reduced the weight and the number of plugs of seminal material emitted by the CDP-injected animals. The possible involvement of the serotonergic system in determining the dose-dependent increase in erections and decrease in seminal emission following CDP treatments is discussed. Clinical implications are also briefly considered.