The Antagonizing Mechanism of Acetylcholine on the Atrial Non-Pacemaker Potentials Depressed by Adrenolytics

Recovering Effect of Acetylcholine on the Depressed Atrial Transmembrane Potential of the Reserpinized Rabbit by the Adrenolytics

“…3) The recover ing effect of acetylcholine on the configuration of the transmembrane potential was longer-lasting (17). These effects of acetylcholine were observed not only in the un treated atrium but also in the reserpinized one.…”

Effects of Dichloroisoproterenol and Phenoxy Benzamine on the Transmembrane Potentials of the Isolated Rabbit’s Heart

“…These effects are presumedly being related with the sympathomimetic effect of Q-receptor blocking agents. The action potential abolished by the a-receptor blocking agents were restarted by ACh (2,3). Several investigators (7)(8)(9)(10) assumed that the stimulating effect of ACh related with endogenously liberated catecholamine.…”

Effects of Carnitine on the Spontaneous Contraction and the Transmembrane Potentials of the Isolated Rabbit’s Atria

“…In -the antagonizing respect, carnitine methyl ester seemed to be more effective than carnitine chloride. The parameters of the transmembrane potential which were measured at the peak effect within 10 minutes after the application of l0' of ACh in the un-treated atria (15) were compared with those in the preparations treated with 10-4 of carnitine methylester and carnitine chloride ( Table 2). The mean decrease in the duration of the action poten tial caused by ACh (10-') in the atria treated with both compounds was 31.8 and 15.7%, respectively.…”

“…The composition of the solution and the method of the recordings were described previously (14,15). The parameters measured for the transmembrane potential were the resting potential and amplitude, 90% duration and repolarization time of the action potential.…”