[Influence of halothane on the effects of endogenous and exogenous noradrenaline on the isolated rabbit heart perfused at constant pressure].
The influence of halothane on the release of noradrenaline from synpathetic nerve endings was studied in isolated rabbit hearts with an intact postganglionic sympathetic nerve supply. In addition we investigated the influence of this anaesthetic on the effects of noradrenaline released from the nerve endings or infused into the aortic cannula. Halothane did not alter the noradrenaline release evoked by electrical stimulation of the postganglionic sympathetic nerve fibres. Although halothane directly diminished the rate of the isolated rabbit heart, the positive chronotropic effect of noradrenaline was not influenced by this anaesthetic. The coronary flow decreased during application of halothane. Both stimulation of postganglionic sympathetic nerve fibres and noradrenaline infusion (250ng/min, lasting for 2 min) evoked a decline in coronary flow; the decrease in coronary flow caused by noradrenaline was markedly attenuated by halothane. This effect of halothane did probably not depend on alterations of the myocardial component of coronary resistance, but on the fact that the vasoconstrictor effect of noradrenaline on the coronary vessels was decreased by this anaesthetic.
D000818:Animals; D003326:Coronary Circulation / Q000187:drug effects; D004347:Drug Interactions; D004558:Electric Stimulation; D005260:Female; D006221:Halothane / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D008297:Male; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism / Q000494:pharmacology* / Q000502:physiology; D010477:Perfusion; D011817:Rabbits; D013564:Sympathetic Nervous System / Q000187:drug effects
D006221:Halothane; D009638:Norepinephrine
Zum Einfluss von Halothan auf die Wirkungen von endogenem und exogenem Noradrenalin am isolierten, druckkonstant perfundierten Kaninchenherzen