Yao B, Zheng J L, Qin W, Bian C F
Department of Pharmacology, Xuzhou Medical College.
Yao Xue Xue Bao. 1994;29(7):497-501.
6 beta-AN (6 beta-acetoxy nortropane), a novel selective M2-receptor agonist, caused decrease in FR, TV, MVV and pO2 and increase of pCO2 when intravenous injection of 10 micrograms.kg-1 in conscious rabbits or 2, 5, 20 micrograms.kg-1 in conscious dogs was given (P < 0.05 or 0.01). The inhibitory effect on MVV exhibited a dose-dependent relationship. Small doses of 6 beta-AN icv (0.5, 1, 2, 4 micrograms.kg-1 in the conscious rabbits) and iva (0.25, 0.5 and 1.0 micrograms.kg-1 in anesthetized dogs) decreased FR, TV, MVV and pO2 and increased pCO2 as well. These results were reversed after administration of AF-DX116 and enhanced after administration of pirenzepine. Thus, it appears that the inhibitory action of 6 beta-AN on respiration might be related to stimulation of the inhibitory M2 cholinergic receptor in respiratory center.
6β-AN（6β-乙酰氧基去甲托烷）是一种新型的选择性M2受体激动剂，当给清醒兔静脉注射10微克/千克或给清醒犬静脉注射2、5、20微克/千克时，可导致呼吸频率（FR）、潮气量（TV）、最大通气量（MVV）和氧分压（pO2）降低，二氧化碳分压（pCO2）升高（P<0.05或0.01）。对MVV的抑制作用呈剂量依赖性关系。小剂量的6β-AN经脑室内注射（清醒兔为0.5、1、2、4微克/千克）和静脉注射（麻醉犬为0.25、0.5和1.0微克/千克）也会降低FR、TV、MVV和pO2，并升高pCO2。给予AF-DX116后这些结果会逆转，给予哌仑西平后则会增强。因此，6β-AN对呼吸的抑制作用似乎可能与刺激呼吸中枢的抑制性M2胆碱能受体有关。
