Journal of Clinical Endocrinology & Metabolism, Vol 71, 187-192, Copyright © 1990 by Endocrine Society

ARTICLES

Effects of insulin-induced hypoglycemia on beta 2-adrenoceptor density and proliferative responses of human lymphocytes

LJ van Tits, A Daul, HJ Bauch, H Grosse-Wilde, M Happel, MC Michel and OE Brodde
Zentrum fur Innere Medizin, Universitat Essen, West Germany.

We studied the effects of insulin (0.1 IU/kg BW, iv)-induced hypoglycemia on lymphocyte beta 2-adrenoceptor function, lymphocyte subset distribution, and proliferative response to mitogen stimulation in 10 healthy volunteers. Thirty minutes after insulin injection plasma glucose levels were markedly decreased; concomitantly, plasma epinephrine levels had increased about 10-fold; plasma norepinephrine levels, however, increased only moderately. Lymphocyte beta 2- adrenoceptor density and the cAMP response to 10 mumol/L isoproterenol stimulation were elevated; lymphocyte Ts/c-cells had increased, whereas Th-cells had decreased, resulting in a decrease in the Th-/Ts/c-cell ratio from 1.7 to 1.0. These changes were accompanied by a significantly reduced lymphocyte proliferative response (measured as [3H]thymidine uptake) to mitogen stimulation. Two hours after insulin injection plasma catecholamines, lymphocyte beta 2-adrenoceptor function, lymphocyte subset distribution, and proliferative responses had returned to nearly preinsulin levels. We conclude that acute vigorous increases in endogenous epinephrine evoked by insulin-induced hypoglycemia are associated with increases in lymphocyte beta 2- adrenoceptor function, redistribution of lymphocyte subsets, and an (at least transiently) attenuated in vitro immune responsiveness.