Ito Shinobu, Mori Tomohisa, Sawaguchi Toshiko
Department of Legal Medicine, Tokyo Women's Medical University, Tokyo, Japan.
Behav Pharmacol. 2006 Dec;17(8):691-701. doi: 10.1097/FBP.0b013e32801155a1.
Interactions between the dopaminergic system and opioids have not been adequately clarified. The present study was designed to investigate the effects of micro-opioid (morphine), delta-opioid (SNC80) and kappa-opioid (U50 488H) receptor agonists on dopamine receptor agonist-induced climbing behavior in mice. Apomorphine (dopamine-receptor agonist) increased stereotyped climbing behavior, unlike methamphetamine, morphine, U-50 488H and (+/-)7-hydroxy-N,N-di-n-propyl-2-aminotetralin hydrobromide (D2-like receptor agonist). Furthermore, SKF81297 (D1 receptor agonist) and SNC80 caused climbing behavior. In addition, while morphine (20 mg/kg), but not U50 488H or SNC80, significantly attenuated high-dose apomorphine (2.0 mg/kg)-induced climbing behavior, it significantly potentiated low-dose apomorphine (0.5 mg/kg)-induced climbing behavior. These results suggest that morphine may have dual effects on the behavioral effects induced by apomorphine. Furthermore, we interestingly showed that the combination of apomorphine or SKF81297 and SNC80 enhanced frequent nonstereotypic climbing behavior, suggesting that delta/D1 interactions may play a prominent role in the expression of certain types of behavior in mice. Thus, micro-opioid, delta-opioid and kappa-opioid receptor agonists induce possible differential effects on the dopaminergic system in mice.
多巴胺能系统与阿片类药物之间的相互作用尚未得到充分阐明。本研究旨在探究微阿片（吗啡）、δ阿片（SNC80）和κ阿片（U50 488H）受体激动剂对多巴胺受体激动剂诱导的小鼠攀爬行为的影响。与甲基苯丙胺、吗啡、U-50 488H和（±）7-羟基-N，N-二正丙基-2-氨基四氢萘氢溴酸盐（D2样受体激动剂）不同，阿扑吗啡（多巴胺受体激动剂）增加了刻板攀爬行为。此外，SKF81297（D1受体激动剂）和SNC80引起了攀爬行为。另外，虽然吗啡（20mg/kg）可显著减弱高剂量阿扑吗啡（2.0mg/kg）诱导的攀爬行为，但U50 488H或SNC80则无此作用，而吗啡却显著增强了低剂量阿扑吗啡（0.5mg/kg）诱导的攀爬行为。这些结果表明，吗啡可能对阿扑吗啡诱导的行为效应具有双重作用。此外，我们有趣地发现，阿扑吗啡或SKF81297与SNC80联合使用可增强频繁的非刻板攀爬行为，这表明δ/D1相互作用可能在小鼠某些类型行为的表达中起重要作用
