• Media type: E-Article
  • Title: Effects of clenbuterol on insulin resistance in conscious obese Zucker rats
  • Contributor: Pan, Shujia J.; Hancock, Joe; Ding, Zhenping; Fogt, Donovan; Lee, Mancheong; Ivy, John L.
  • Published: American Physiological Society, 2001
  • Published in: American Journal of Physiology-Endocrinology and Metabolism, 280 (2001) 4, Seite E554-E561
  • Language: English
  • DOI: 10.1152/ajpendo.2001.280.4.e554
  • ISSN: 0193-1849; 1522-1555
  • Origination:
  • Footnote:
  • Description: The present study was conducted to determine the effect of chronic administration of the long-acting β2-adrenergic agonist clenbuterol on rats that are genetically prone to insulin resistance and impaired glucose tolerance. Obese Zucker rats ( fa/fa) were given 1 mg/kg of clenbuterol by oral intubation daily for 5 wk. Controls received an equivalent volume of water according to the same schedule. At the end of the treatment, rats were catheterized for euglycemic-hyperinsulinemic (15 mU insulin · kg−1· min−1) clamping. Clenbuterol did not change body weight compared with the control group but caused a redistribution of body weight: leg muscle weights increased, and abdominal fat weight decreased. The glucose infusion rate needed to maintain euglycemia and the rate of glucose disappearance were greater in the clenbuterol-treated rats. Furthermore, plasma insulin levels were decreased, and the rate of glucose uptake into hindlimb muscles and abdominal fat was increased in the clenbuterol-treated rats. This increased rate of glucose uptake was accompanied by a parallel increase in the rate of glycogen synthesis. The increase in muscle glucose uptake could not be ascribed to an increase in the glucose transport protein GLUT-4 in clenbuterol-treated rats. We conclude that chronic clenbuterol treatment reduces the insulin resistance of the obese Zucker rat by increasing insulin-stimulated muscle and adipose tissue glucose uptake. The improvements noted may be related to the repartitioning of body weight between tissues.
  • Access State: Open Access