Research Article

An Inotropic Action Caused by Muscarinic Receptor Subtype 3 in Canine Cardiac Purkinje Fibers

Figure 1

Inotropic effects of ACh on canine cardiac Purkinje fibers and effects of pretreatment with atropine on the ACh-evoked responses. (a) Typical tracings of effects of cumulatively applied ACh and atropine pretreatment on ACh-evoked inotropy. (b) Typical tracings of single application of ACh 10−4 M on the inotropy.