Open AccessIn Vivo Response to α 1 ‐Adrenoreceptor Stimulation in Human White Adipose Tissue
Author(s) -
Boschmann Michael,
Krupp Götz,
Luft Friedrich C.,
Klaus Susanne,
Jordan Jens
Publication year - 2002
Publication title -
obesity research
Language(s) - English
Resource type - Journals
eISSN - 1550-8528
pISSN - 1071-7323
DOI - 10.1038/oby.2002.75
Subject(s) - phenylephrine , propranolol , endocrinology , white adipose tissue , adipose tissue , medicine , lipolysis , chemistry , stimulation , microdialysis , blood pressure , central nervous system
Objective: Recent studies in rats suggest an important effect of α 1 ‐adrenoreceptor stimulation on glucose uptake in white adipocytes. It is not known if α 1 ‐adrenoreceptor stimulation elicits similar metabolic effects in humans. Research Methods and Procedures: Three microdialysis catheters in abdominal subcutaneous adipose tissue were perfused with 0.00, 0.01, 0.10, 1.00, and 10.00 μM isoproterenol, phenylephrine, or phenylephrine plus 100 μM propranolol. Dialysate concentrations of ethanol, glycerol, glucose, and lactate were measured for estimating blood flow (ethanol‐dilution technique), lipolysis, and glycolysis, respectively. Results: Phenylephrine, with or without propranolol, did not elicit a change in ethanol ratio. In contrast, the ethanol ratio decreased markedly with isoproterenol. Dialysate glucose concentration decreased with phenylephrine with and without propranolol and increased with isoproterenol. Phenylephrine caused a dose‐dependent increase in dialysate glycerol concentration, with a maximal effect similar to that of isoproterenol. The effect was attenuated with propranolol. Discussion: Our findings suggest that α 1 ‐adrenoreceptor stimulation by phenylephrine increases glucose uptake and metabolism in human abdominal adipose tissue. Furthermore, phenylephrine elicits a marked increase in lipolytic activity in white adipose tissue through β‐adrenoreceptor activation.