The interaction of glucagon with theophylline, PGE1, isoproeerenol, ouabain, and CaC1 on the dog isolated papillary muscle.
نویسندگان
چکیده
Michael J. Antonaccio and Benedict R. Lucchesi Department of Pharmacology, The University of Michigan Medical School, Ann Arbor, Michigan 48104 (Received 22 May 1970 ; in final form 3 August 1970) Glucagon has been shown to be both a positive inotropic and chronotropic agent in many species including man (1-5). However, the positive inotropic effect of glucagon on dog papillary muscles can be reversed by previous exposure of the tissues to a relatively high concentration of ouabain (2). The purpose of this study was to determine the interactions of glucagon on dog isolated papillary muscles with other positive inotropic agents which presumably have a different mechanism of action .
منابع مشابه
Cardiac actions of glucagon.
Glucagon increased heart rate and contractile force in the anesthetized dog and increased isometric tension in the isolated dog papillary muscle. The positive inotropic and chronotropic responses were not abolished or reduced by previous administration of the beta-receptor blocking agent propranolol, in doses of 0.5 mg/kg. Glucagon increased the force and rate of cardiac contraction even when c...
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عنوان ژورنال:
- Life sciences. Pt. 1: Physiology and pharmacology
دوره 9 19 شماره
صفحات -
تاریخ انتشار 1970