APStracts 2:0204H, 1995.

Muscle metaboreceptors in the hemodynamic, autonomic and ventilatory responses to exercise in men. Piepoli, Massimo, Andrew L. Clark, and Andrew J. S. Coats. Cardiac Medicine, Royal Brompton National Heart & Lung Institute, London, and Cardiovascular Medicine, John Radcliffe Hospital, Oxford, U.K.

APStracts 2:0204H, 1995.

A muscle metaboreceptor (ergoreceptor) contribution to the hemodynamic and autonomic responses to exercise is well recognised but a ventilatory component remains controversial. Control handgrips were compared to handgrips followed by 4 minute regional circulatory occlusion of the exercising muscles, to isolate the metaboreceptor role in blood pressure, autonomic tone (spectral analysis of R-R and blood pressure variability) and ventilatiory responses to exercise in 11 normals. Exercise responses were maintained after the effort by metaboreflex activation, in systolic pressure (136.2+/-3.5 vs. 123.0+/-4.3 mmHg, p<0.05), ventilation (19.0+/-2.6 vs. 8.5+/-0.4 l min-1, p<0.0005) and sympathetic discharge to the heart and circulation (elevated Low Frequency components of R-R interval, 1747.5+/-309.2 vs. 1085.9+/-259.1 msec2, p<0.05, and systolic pressure variability, 45.3+/-3.9 vs. 26.5+/-4.4 mmHg2, p<0.005) We conclude that metaboreflex contributes to the sympathetic, hypertensive and hyperpneic responses to exercise in normals.

Received 3 November 1994; accepted in final form 8 May 1995.
APS Manuscript Number H984-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 26 May 1995.