Wheeler M A, Solomon R A, Cooper C, Hertzberg L, Mehta H, Miki N, Bitensky M W
J Infect Dis. 1976 Mar;133 Suppl:89-96. doi: 10.1093/infdis/133.supplement_1.s89.
Three discrete phases are discernible in the activation, by Vibrio cholerae toxin, of adenylate cyclase in fragments of sarcoma 180 cell membranes. In the first, or preparatory, phase the toxin must be exposed to dithiothreitol or nicotinamide adenine dinucleotide (NAD) in the absence of the membranes. In the second phase, the prepared toxin is dissociated to yield a macromolecular cyclase-activating factor (MCAF) in the presence of the membranes. In the third phase, membrane basal adenylate cyclase is activated by MCAF in the presence of NAD. The integrity of the catecholamine or beta-receptor associated with sarcoma adenylate cyclase is irrelevant in the activation of cyclase by MCAF. This activation proceeds undiminished even if the beta-receptor is desensitized or blocked by propranolol.
在肉瘤180细胞膜片段中，霍乱弧菌毒素激活腺苷酸环化酶可分为三个不同阶段。在第一个阶段，即准备阶段，毒素必须在无细胞膜的情况下与二硫苏糖醇或烟酰胺腺嘌呤二核苷酸（NAD）接触。在第二阶段，制备好的毒素在有细胞膜存在时解离，产生一种大分子环化酶激活因子（MCAF）。在第三阶段，膜基础腺苷酸环化酶在NAD存在时被MCAF激活。与肉瘤腺苷酸环化酶相关的儿茶酚胺或β受体的完整性在MCAF激活环化酶过程中无关紧要。即使β受体被普萘洛尔脱敏或阻断，这种激活仍能不受影响地进行。
