中枢D_1和D_2亚型多巴胺受体与左旋四氢巴马汀镇痛的关系  

RELATIONSHIP BETWEEN CENTRAL D_1 AND D_2 SUBTYPE DOPAMINE RECEPTORS AND L-TETRAHYDROP-ALMATINE-PRODUCED ANALGESIA

作　　者：吴钢[1] 姜建伟[1] 吴根诚[1] 曹小定[1] 

机构地区：[1]上海医科大学基础医学部神经生物学教研室

出　　处：《上海医科大学学报》1991年第5期329-334,共6页Journal of Fudan University(Medical Science)

基　　金：国家七五攻关课题基金(75-64-01-09)

摘　　要：在兔耳K^+透入测痛模型上,左旋四氢巴马汀(1-THP,8mg/kg,iv)的镇痛作用被双侧脑室注射多巴胺(DA)受体广谱激动剂DA或去水吗啡(Apo)以及选择性D_1受体激动剂SKF-38393减弱,被选择性D_2受体激动剂喹吡罗加强。另外,采用放射免疫分析和高效液相色谱——电化学检测法分别观察到1-THP镇痛时脑脊液中cAMP含量降低,及DA及其代谢产物DOPAC含量升高。提示1-THP镇痛与中枢D_1和D_2亚型DA受体有关,其中D_1受体的阻断导致其镇痛,而D_2受体的阻断不利于其镇痛。Analgesia was measured by potassium iontophoretic dolorimetry. It was found that the analgesia produced by administration of l-tetrahydropalmatine(1-THP, 8mg/kg, iv)in rabbits was markedly antagonized by intracerebroventricular injection(icv) of dopamine (DA) and apomorphine (Apo) (both non-selective DA receptor agonists) as well as SKF-38393 (a selective D1 receptor agonist). But. analgesia was significantly augmented by iov quipirole (Qui, LY-171555), a selective D2 receptor agonist. In addition, by using radio-immunoassay, it was shown that t-THP (8 mg/mg, iv) caused a decrease in CSF cAMP content, and this effect was negatively correlated to changes in the pain threshold (r = - 0.789, P< 0.01), suggesting that 1-THP-produced analgesia may be mediated by the-blockade of D1 receptor. By Using high performance liquid ohromatography, it was found that 1-THP (8mg/kg, iv) broght forth elevation of DA and its metabolite DOPAO contents in CSF. There was a negative correlation between ohangs of DA content and ohangsin pain threshold after 1-THP administration (r=- 0.801, P<0.05), suggesting that the blockade of D3 receptor is involved in 1-THP-produced anagesia as well. All these results indicate that 1-THP-produced analgesia might be related to the central D1 and D2 subtype DA receptors which exert opposite effects on analgesic effects.

关 键 词：多巴胺 四氢巴马汀 止痛 受体 

分 类 号：R966[医药卫生—药理学]