脊髓蛛网膜下腔注射mu和Kappa阿片激动剂PL 017和66A-078引起大鼠血压降低

LOWERING OF ARTERIAL BLOOD PRESSURE IN RATS BY INTRATHECAL INJECTION OF MU AGONIST PL017 AND KAPPA AGONIST 66A-078

用脊髓蛛网膜下腔(ith)插管和注射的方法,观察了mu(μ)型阿片受体激动剂PLO 17和Kappa(k)型阿片受体激动剂 66A-078对大鼠平均动脉血压(MAP)的影响。结果表明:PL017 2.5～10μg或66A-078 0.25～4μg可使大鼠MAP显著下降,呈量-效关系。用特异性μ或k阿片受体拮抗剂可预防或翻转此作用。静脉(iv)注射PL017 10μg和66A-078 4μg并不引起MAP的明显降低。本文结果提示:大鼠脊髓中的μ和k阿片受体具有心血管抑制作用。

Intrathecal (ITH) injection of PL017, a potent and specific agonist for mu receptor, and 66A-078,a metabolically stable analogue of dynorphin-A, resulted in a dramatic decrease in mean arterialpressure (MAP) of nembutal anaesthetized male rats. PL017 at doses of 2.5-10 μg, 66A-078 at doses of 0.25-4 μg produced a dose-dependent decreaseof MAP, the depressor effect of PL017 and 66A-078 were prevented or reversed by their specificantagonists β-FNA and nor-BNI, respectively. Intravenous injection of the centrally effective doseproduced no significant depressor effect. It is concluded that mu and kappa opioid receptors in thespinal cord of rat seem to mediate a suppressive effect on cardiovascular activities.