Stereoselective discriminative stimulus effects of zopiclone in rhesus monkeys.
Stereoselective discriminative stimulus effects of zopiclone in rhesus monkeys.
复制标题
佐匹克隆对恒河猴的立体选择性辨别刺激作用。
DOI：
10.1007/s00213-002-1286-9
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
France,CharlesP
中科院分区：
文献类型：
--
作者：
McMahon,LanceR;Jerussi,ThomasP;France,CharlesP
AbstractRationale.The behavioral effects of racemic zopiclone are similar to those of benzodiazepines that positively modulate GABA at the GABAAreceptor complex; however, it is not clear how enantiomers or metabolites of zopiclone contribute to the benzodiazepine-like behavioral effects of racemic zopiclone.Objectives.Racemic zopiclone, its (R)- and (S)- enantiomers, and the (S)-N-desmethyl metabolite, were evaluated for discriminative stimulus effects in untreated and diazepam treated rhesus monkeys.Methods.One group of monkeys discriminated the benzodiazepine midazolam and another group, treated daily with the benzodiazepine diazepam (5.6 mg/kg, PO), discriminated the benzodiazepine antagonist flumazenil.Results.(RS)-Zopiclone (0.32–17.8 mg/kg) and (S)-zopiclone (0.1–10 mg/kg) substituted with similar potencies for midazolam (≥80% midazolam-appropriate responding). The midazolam-like discriminative stimulus effects of (RS)-zopiclone were antagonized by flumazenil (pKB=7.52). (R)-Zopiclone occasioned a maximum 45% midazolam-appropriate responding at a dose of 100 mg/kg; (S)-desmethylzopiclone produced saline-appropriate responding up to a dose of 100 mg/kg. All four test compounds occasioned predominantly vehicle-appropriate responding in diazepam treated monkeys discriminating flumazenil. (RS)-Zopiclone (10 mg/kg) attenuated the discriminative stimulus effects of flumazenil in diazepam treated monkeys.Conclusions.These results clearly demonstrate that in rhesus monkeys the discriminative stimulus effects of zopiclone are stereoselective and qualitatively similar to those of midazolam. These results fail to show any benzodiazepine-like or benzodiazepine antagonist-like discriminative stimulus effects for (S)-N-desmethylzopiclone, suggesting that any behavioral (e.g. anxiolytic) effects of this compound are not the result of actions at benzodiazepine receptors.
