Cardiac electrophysiological effects of U-50,488H on guinea-pig papillary muscle.
Intracellular microelectrodes were used to study the electrophysiological effects of U-50,488H on guinea-pig papillary muscle. U-50,488H (10(-5) M) caused a significant decrease in the maximum rate of depolarization and a decrease in the action potential duration. At high concentration (5 x 10(-5) M) U-50,488H induced a significant decrease of resting potential, maximum rate of depolarization, action potential amplitude and the action potential duration. The administration of MR-2266 (5 x 10(-7) M) partially antagonized the cardiac electrophysiological effects of U-50,488H. These results suggest that the electrophysiological effects of U-50,488H may be partially due to an interaction with opioid receptors.
Department of Physiology and Pharmacology, School of Medicine, Murcia, Spain.
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Alarcón
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Hernández
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Laorden
D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001575:Benzomorphans / Q000494:pharmacology; D006168:Guinea Pigs; D008564:Membrane Potentials / Q000187:drug effects; D009292:Narcotic Antagonists / Q000494:pharmacology; D010210:Papillary Muscles / Q000187:drug effects*; D011759:Pyrrolidines / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D017473:Receptors, Opioid, kappa / Q000037:antagonists & inhibitors* / Q000502:physiology; D016278:Ventricular Function, Right / Q000187:drug effects*
D001575:Benzomorphans; D009292:Narcotic Antagonists; D011759:Pyrrolidines; D017473:Receptors, Opioid, kappa; C027247:MR 2266; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer