乙酰胆碱及其受体亚型阻滞剂对大鼠皮层体感区Ca^(2+),Mg^(2+)-ATP酶活性的影响

Effect of acetylcholine and ACh receptor antagonists on Ca^(2+),Mg^(2+)-ATPase activity in rat cerebral cortex

目的观察脑室注射乙酰胆碱及其受体亚型阻滞剂对大鼠皮层体感区Ca2+,Mg2+-ATP酶活性的影响,探讨乙酰胆碱中枢作用的可能机制。方法脑室注射ACh及其受体亚型阻滞剂后,采用定磷法检测Wistar大鼠皮层体感区Ca2+,Mg2+-ATP酶活性。结果①脑室注射20μg/10μl的乙酰胆碱可使Ca2+,Mg2+-ATP酶活性由脑室注射等量生理盐水的(8.271±1.298)μmolpi/mgprot升高到(16.444±3.270)μmolpi/mgprot(P<0.05,n=5);②两侧脑室同时分别注射6.4μg/10μl N受体阻滞剂维库溴铵和乙酰胆碱可使Ca2+,Mg2+-ATP酶活性由脑室注射乙酰胆碱的(16.444±3.270)μmolpi/mgprot降低到(8.854±1.366)μmolpi/mgprot(P<0.05,n=5);③两侧脑室同时分别注射3.5μg/10μl M1受体阻滞剂哌仑西平和乙酰胆碱或分别注射4.5μg/10μl M3受体阻滞剂4-DAMP和乙酰胆碱均可使Ca2+,Mg2+-ATP酶活性不同程度降低,但与脑室单独注射乙酰胆碱相比无显著差异(P>0.05,n=5)。结论乙酰胆碱在大鼠大脑皮层体感区的效应,主要是通过N型受体实现的。

Objective To investigate the effect of intracerebroventricular injection of acetylcholine and ACh receptor antagonists on Ca^2＋,Mg^2＋ -ATPase activity in rat cerebral cortex. Methods The activity of Ca^2＋,Mg^2＋ -ATPase of rat cerebral cortex was measured by determining the Pi. Results ①After intracerebroventricular injection of acetylchline 20 μg/10μl, as compared with the control group, the Ca^2＋ , Mg2^＋ -ATPase activity was gready increased from （8. 271 ± 1. 298） μmolpi/mgprot to （ 16. 444 ＋ 3. 270） μmolpi/mgprot （ P 〈 0.05, n = 5） ;②After intracerebroventricular injection of nicotinic acetylchline receptor antagonist vecuronium bromide 6.4μg/10μl and ACh 20μg/10μl, as compared with the ACh group, the Ca^2＋, Mg^2＋ -ATPase activity was gready reduced to （8. 854 ± 1. 366）tnnolpi/mgprot （P 〈 0.05, n = 5） ; ③After intracerebroventricular injection the selective M1 ACh receptor antagonist pirenzepine 3.5 μg/10μl and acetylchline 20μg/10μl, the Muscarinic receptor antagonist 4-DAMP 4.5μg/10μl and acetylchline 20μg/10μl, respectively, the Ca^2＋,Mg^2＋ -ATPase activity was changed insignificantly（ P 〉 0.05, n = 5）. Conclusion It is suggested that the effect of ACh on the rat cerebral cortex is probably mediated by the ACh N receptor.