作者: GERALD GLICK , EUGENE BRAUNWALD , Robert M. Lewis
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摘要: This study was designed to define the relative roles of sympathetic and parasympathetic nervous systems in reflex alterations heart rate consequent changes arterial pressure. In 23 experiments carried out on 22 anesthetized dogs studies performed four trained, unanesthetized dogs, acute pressure were produced by administering drugs acting peripheral vascular bed. The effects acutely elevating systemic also investigated intact human subjects. Augmenting above control levels with graded doses phenylephrine always slowed strikingly. Although complete blockade guanethidine or pronethalol did not significantly alter degree slowing, atropine vagotomy essentially abolished this response. Conversely, lowering intravenous injections nitroglycerin raised state, a response nethalide, but atropine. Thus, when rises control, decrease is mediated system, withdrawal activity playing no detectable role; falls below levels, elevation primarily system. These findings are consonant traditional concept which predicates simultaneous reciprocal occurring two components autonomic