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Updated: Aug 10, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
Modulatory effects of diltiazem on inotropic responses to amrinone on rabbit isolated atria
S M Parhate1, V R Thawani, V M Motghare
1Department of Pharmacology, Govt. Medical College, Nagpur.
Abstract:
The effect of pretreatment with graded concentration of diltiazem on the inotropic responses to amrinone were studied on isolated atria of rabbit. The responses to amrinone were modified by diltiazem in a biphasic manner; initial potentiation followed by inhibition. The potentiation is proposed to be due to synergistic rise in cytosolic calcium ion concentration by diltiazem and amrinone. The inhibition by diltiazem in higher concentration may be due to blockade of calcium ion influx and depletion of intracellular calcium ion from storage sites.
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