OBJECTIVE: Recent studies in rats suggest an important effect of alpha(1)-adrenoreceptor stimulation on glucose uptake in white adipocytes. It is not known if alpha(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 microM isoproterenol, phenylephrine, or phenylephrine plus 100 microM 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 alpha(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 beta-adrenoreceptor activation.
OBJECTIVE: Recent studies in rats suggest an important effect of alpha(1)-adrenoreceptor stimulation on glucose uptake in white adipocytes. It is not known if alpha(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 microM isoproterenol, phenylephrine, or phenylephrine plus 100 microM 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 alpha(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 beta-adrenoreceptor activation.
Authors: Andreas L Birkenfeld; Michael Boschmann; Cedric Moro; Frauke Adams; Karsten Heusser; Jens Tank; André Diedrich; Christoph Schroeder; Gabi Franke; Michel Berlan; Friedrich C Luft; Max Lafontan; Jens Jordan Journal: J Clin Endocrinol Metab Date: 2006-09-19 Impact factor: 5.958
Authors: Frauke Adams; Michael Boschmann; Elmar Lobsien; Andreas Kupsch; Axel Lipp; Gabriele Franke; Marie Charlotte Leisse; Juergen Janke; Simone Gottschalk; Joachim Spranger; Jens Jordan Journal: Eur J Clin Pharmacol Date: 2008-07-30 Impact factor: 2.953
Authors: Uwe Schumann; Christopher P Jenkinson; Andreas Alt; Martina Zügel; Jürgen M Steinacker; Marion Flechtner-Mors Journal: PLoS One Date: 2017-03-27 Impact factor: 3.240