Location of Repository

Central and peripheral adrenoceptors affect glucose, free fatty acids, and insulin in exercising rats

By A.J.W. Scheurink, A.B. Steffens and L. Benthem

Abstract

The effects of intravenously and intrahypothalamically administered α- and β-adrenoceptor antagonists on exercise-induced alterations in blood glucose, plasma free fatty acids (FFA), and insulin were investigated in rats. Exercise consisted of strenuous swimming against a counter current for 15 min. Before, during, and after swimming, blood samples were withdrawn through a permanent heart catheter. Intravenous administration of the α-blocker phentolamine led to a reduction in glucose and a substantial increase in insulin levels. Infusion of phentolamine through permanent bilateral cannulas into either the ventromedial or lateral area of the hypothalamus (VMH and LHA, respectively) completely prevented the increase in glucose while the decline in insulin was unaffected. Infusion of phentolamine into the VMH caused much higher plasma FFA levels than in controls. The β-blocker timolol given intravenously caused a delayed increase in glucose and prevented the increase in FFA. Infusion of timolol into either VMH or LHA caused a delay in the increase in both glucose and FFA. The results suggest that 1) both peripheral and hypothalamic adrenoceptors are involved in energy metabolism during exercise and 2) FFA, glucose, and insulin concentrations in blood are independently regulated by VMH and LHA.

Year: 1988
OAI identifier: oai:ub.rug.nl:dbi/4d02335e5950d
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://cbn.eldoc.ub.rug.nl/roo... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.