乙酰胆碱的α受体效应

THE RESPONSE OF α RECEPTOR TO ACETYLCHOLINE

ACh 在10^(-7)～10^(-3)mol/L 时,可使以α受体为主的离体小鼠输精管收缩,呈量-效关系(pD_2=4.2257);与同样浓度的 NE 无显著差异;M 受体激动剂匹罗卡品则使其舒张.该作用在利血平耗竭 CA 后制备的标本上,或以箭毒阻断 N 受体时依然存在;但可被阿托品(pA_2=8.3146)、酚妥拉明(pA_2=5.3526)和异博定(pA_2=5.3377)阻断.表明 ACh 可作用于输精管的α受体使其收缩.

At the concentration of 10^(-7)mol/L-10^(-3)mol/L,ACh could induce contraction of a receptor-dominating spermatic ducts of mice in vitro with a dose-response relation similar to that induced by NE at the same concentration,while pilocarpine,the agonist of M receptor,could in- duce dilatation in the same samples.When the N receptor was blocked by curarine,or on the sam- ples made after the CA had been exhausted by reserpine,the contraction still existed,but could be blocked by atropine(pA_2=8.3146),phetolamin(pA_2=5.3526),or verapamil(pA_2=5.3377),indi- cating that ACh can act on α receptor in spermatic duct and cause the duct to contract.