TY - JOUR AU - Ji Guang-Ju AU - Zhao De-Hua AU - Liu De-Qiang AU - Sheng Bao-Heng PY - 2016 TI - Effects of 3,6-dimethylamino-dibenzopyriodonium edetate on action potentials in guinea pig papillary muscles JF - Acta Pharmacologica Sinica; Vol 14, No 2 (March 1993): Acta Pharmacologica Sinica Y2 - 2016 KW - N2 - The effects of 3,6-dimethylamino-dibenzopyriodonium edetate (IHC-72) on action potentials (AP) and slow response action potentials of guinea pig papillary muscles were studied with intracellular microelectrodes. IHC-72 12.7, 25.4, and 50.8 mumol.L-1 decreased the maximal upstroke velocity (Vmax), amplitude of action potential (APA), over shot (OS), and resting potential (RP) while prolonged the action potential duration at 30%, 50%, 90%, and 100% repolarization (APD30, APD50, APD90, and APD100). IHC-72 25.4 and 50.8 mumol.L-1 decreased the APA, Vmax, and prolonged APD50 and APD90 under high K+ superfusion. IHC-72 25.4 and 50.8 mumol.L-1 depressed the automaticity, APA, and maximal diastolic potential (MDP) of the slow response action potentials induced by BaCl2. The results indicated that IHC-72 might nonspecifically inhibit the transmembrane movement of Ca2+, Na+, and K+. UR - http://www.chinaphar.com/article/view/8719