【摘要】 目的：研究脑桥-延髓中M受体亚型与环核苷酸的关系.方法:大鼠ip药物,脑桥-延髓等组织中cGMP和cAMP含量分别用放射免疫法和竞争性蛋白结合法测定,对照组ip生理盐水.结果:ip匹鲁卡品,脑桥-延髓中cGMP含量增加,cAMP变化不明显,ip哌仑西平或东莨菪碱可拮抗之.ip 6β-乙酰氧基去甲托烷12μg kg^-1,脑桥-延髓中cAMP含量减少,而25 μg kg^-1使cAMP和cGMP均减少,ip AFDX 116或阿托品可拮抗之.结论:激动脑桥-延髓中M₁受体使cGMP增加,激动M₂受体使cGMP和cAMP减少.更多还原

【Abstract】 AIM:To study the relationship between mus-carinic receptor (M-R) subtypes and cyclic nucleotides in pons-medulla oblongata (MeOb).METHODS:The contents of cGMP and cAMP in Sprague-Dawley rat pons-MeOb, cerebellum and cerebral cortex were assayed by radioimmunoassay and competitive protein-binding assay, respectively, after ip injections of drugs. Control rats were given ip normal saline. RESULTS: M1-R agonist pilocarpine (6, 15 mg kg-1, ip) increased the content of cGMP in the pons-MeOb and cerebral cortex, but did not bring about any noticeable change in the cAMP content. The increase of cGMP was antagonized by ip piren-zepine or scopolamine. On the other hand, ip M2-R agonist 6β-acetoxy nortropane (6β-AN) 25 μg kg-1 reduced not only cAMP contents in the pons-MeOb and cerebellum but also cGMP contents in the pons-MeOb and cerebral cortex,while 6β-AN 12μg kg-1 only lowered cAMP content. The decreases of cGMP and cAMP induced by 6β-AN were antagonized by ip AF-DX 116 or atropine, respectively.CONCLUSION: Stimulation of M1-R causes the increase of cGMP and that of M2-R induces the decreases of both cGMP and cAMP in the pons-MeOb.更多还原