Macleod K M
Eur J Pharmacol. 1984 Dec 15;107(1):95-9. doi: 10.1016/0014-2999(84)90096-7.
The ability of the muscarinic agonist, carbachol, to overcome increases in tension and in cAMP produced in response to the adenylate cyclase activator, forskolin, in rabbit papillary muscles was measured. Forskolin alone increased cAMP levels to a much greater extent than did a concentration of isoproterenol that produced an equivalent increase in tension. Carbachol completely overcame the increase in tension, while having no effect on the increase in cAMP, produced by forskolin. The response to carbachol was associated with a significant increase in cGMP levels. It appears that carbachol may block the inotropic response to forskolin by antagonizing the effects of forskolin-induced increases in cAMP.
测定了毒蕈碱激动剂卡巴胆碱克服家兔乳头肌中因腺苷酸环化酶激活剂福斯高林产生的张力增加和环磷酸腺苷（cAMP）增加的能力。单独使用福斯高林使cAMP水平升高的程度比产生同等张力增加的异丙肾上腺素浓度要大得多。卡巴胆碱完全克服了由福斯高林引起的张力增加，而对福斯高林引起的cAMP增加没有影响。对卡巴胆碱的反应与环磷酸鸟苷（cGMP）水平的显著升高有关。似乎卡巴胆碱可能通过拮抗福斯高林诱导的cAMP增加的作用来阻断对福斯高林的变力反应。
