摘要
放射受体结合试验表明大鼠大脑皮层存在M_1受体(约90％)、M_2受体(约10％);东莨菪碱对M_1受体亲和力高于M_2受体,阿托品对M_2受体亲和力高于M_1受体。观察脑电及行为改变,激动M_1受体致中枢兴奋,激动M_2受体致中枢抑制,阻断之则作用相反。东莨菪碱、阿托品中枢作用的不同可能与分别阻滞M_1、M_2受体有关。
Radioligand binding experiments using 8H-QNB and 8H-PZ were performed on the cortex and hippocampus and the cerebellum of Wistar rat brains.It was found that the M1 receptor accounted for approximately 90% the total muscar-inic receptors in the cortex and hippocmpus,and M2 accounted for only about 10 %.When separate scopolamine,atropine,pirenzepine and AF-DX 116 were added to compete against the 8H-labelled reagents in binding to the receptors in the two parts of brain,the pki values obtained suggest that the affinity of scopolamine for M1 is higher than for M2 receptors,and the affinity of atropine for M2 is higher than for M1.In the conscious rabbits with preset electrodes, EEG was recorded and motor activities were observed. When pilocarpine was given, excitatory effects were observed on EEG and motor activities.When 8310 was given,the effects were inhibitory.These results, however,were reversed when M1 and M2 receptors were blocked by adding PZ and AF-DX 116 separately.Thus it can be seen that scopolamine inhibits the EEG and motor activities by blocking the M1 receptor,while the excitatory effect of atropine is brought about by blocking the M2 receptor.
出处
《徐州医学院学报》
CAS
1990年第4期253-257,共5页
Acta Academiae Medicinae Xuzhou
基金
江苏省教育委员会自然科学基金资助课题
关键词
M受体
毛果云香碱
PZ
东茛菪碱
pilocarpine
scopolamine
pirenzepine
8310
atropine
AF-DX 116
M1 receptor
M2 receptor
