AJP - Regulatory, Integrative and Comparative Physiology, Vol 243, Issue 3 379-R382, Copyright © 1982 by American Physiological Society
Beta-adrenergic blockade inhibits thermogenesis and lipolysis during glucoprivation in humans
S. L. Welle, D. A. Thompson and R. G. Campbell
Glucoprivic stress induced by 2-DG (2-deoxy-D-glucose) is associated with
increased oxygen consumption (thermogenesis) and sympathetic nervous system
activity, as well as elevations of circulating levels of various hormones
and metabolic substrates. To examine the role of beta-adrenergic
stimulation in the thermogenic, hyperglycemic, and lipolytic responses to
glucoprivation, we administered intravenous infusions of propranolol or
normal saline (placebo) during 2-DG challenges in seven healthy males. 2-DG
alone produced large increments in plasma catecholamine levels,
hyperglycemia, a 3.5-fold increase in plasma free fatty acid (FFA) levels,
a 15 beat/min increase in pulse rate, and hypothermia in spite of a 20%
increase in oxygen consumption. When propranolol was given, 2-DG produced
only a 50% increase in FFA levels, no change in oxygen consumption, and a
17 beat/min fall in pulse rate associated with a 25% increase in mean
arterial blood pressure. Propranolol only slightly attenuated the
hyperglycemia and hypothermia associated with 2-DG but potentiated the
elevations of plasma epinephrine levels. It is concluded that 2-DG-induced
thermogenesis and lipolysis are primarily dependent on beta-adrenergic
stimulation.
