Abstract: | Male rats were treated with 5 and 10 mg/kg diazepam once daily for 5-30 days. After the drug discontinuation a benzodiazepine receptor antagonist CGS 8216 (2.5-10 mg/kg) induced a behavioural syndrome that might be characterized as an abstinence syndrome. The most typical signs of abstinence were head twitches, myoclonic seizures of forepaws, emotional hyperirritability, increased muscle tone of the tail, sniffing and chewing. These behavioural changes could be observed within 1-1.5 hours after CGS 8216 injection. The abstinence syndrome was induced by repeated CGS 8216 injections for 10-15 days after diazepam discontinuation. Further analysis has shown that that the intensity of abstinence was dependent on the dose and duration of chronic diazepam, as well as on CGS 8216 dose. It is suggested that CGS 8216-induced abstinence syndrome in rats chronically treated with diazepam might be used as a tool for studying the addictive potential of benzodiazepines. |