Autonomic nervous system activity in weight gain and weight loss. Aronne, Louis J., Ronald Mackintosh, Michael Rosenbaum, Rudolph L. Leibel, and Jules Hirsch. Laboratory of Human Behavior and Metabolism, Rockefeller University, 1230 York Avenue Box 181, New York, New York 10021 -6399
APStracts 2:0048R, 1995.
Studies in both animals and humans indicate that the autonomic nervous system (ANS) responds to changes in systemic energy balance. In the present study, ANS response to weight change was examined by sequential blockade of cardiac autonomic innervation with parasympathetic (atropine) and sympathetic (esmolol) blockers. Change in heart period (inter-beat interval) from baseline after atropine defined the amount of parasympathetic control (PC), and the subsequent change after esmolol defined the amount of sympathetic control (SC). In non-obese subjects, weight gain to 10% above initial body weight resulted in a decrease in PC and an increase in SC, and conversely, weight loss to 10% below initial weight resulted in an increase in PC and a decrease in SC. In obese subjects, weight loss resulted in the same pattern of changes in PC and SC. The major changes were in the parasympathetic arm of the ANS. These findings support the hypothesis that the ANS acts to oppose weight change.

Received 23 September 1994; accepted in final form 17 February
1995.
APS Manuscript Number R552-4.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  1 March 1995.