Modulation of vascular tone and glycerol levels measured by in situ
microdialysis in rat adipose tissue.
Darimont, Christian, Perla Saint-Marc, G[acute]erard Ailhaud, and
Raymond Negrel.
Centre de Biochimie (UMR 134 CNRS), Universit[acute]e de Nice -
Sophia Antipolis, Facult[acute]e des Sciences, Parc Valrose, 06108
Nice cedex 2, FRANCE
APStracts 3:0118E, 1996.
Changes in blood flow induced by the [beta]-adrenoceptor agonist,
isoproterenol (Iso), and a stable analogue of the major metabolite of
arachidonic acid in adipose tissue, carbaprostacyclin (cPGI 2 ), have
been studied in rat periepididymal fat pad using in situ
microdialysis, by measuring the distribution ratio of 0.2% ethanol
(O/I ratio) in the dialysate (outflow) versus the perfusate (inflow).
Local perfusions of 1 [mu]M cPGI 2 or 1 ? [mu]M Iso led to reversible
decreases of the O/I ratio which were similar to that induced by the
vasodilating reference drug Hydra (630 ? [mu]M). Interestingly, a
continuous perfusion of Hydra at a submaximal vasodilating
concentration (63 ? [mu]M) was sufficient to prevent further
vasodilatation induced by Iso or cPGI 2 . Taking advantage of this
observation, experiments were designed to evaluate the influence of
the vasodilating effect of Iso or cPGI 2 on their ability to induce
lipolysis in vivo . These results showed that the vasodilating effect
of Iso could contribute to glycerol removal from the extracellular
fluid and demonstrated that, cPGI 2 was devoid of lipolytic activity.
Received 20 November 1995; accepted in final form 4 June 1996.
APS Manuscript Number E548-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 28 June 96