Altered expression of muscle glucose transporter GLUT-4 in diabetic fatty Zucker rats (ZDF/Drt-fa)

Am J Physiol. 1991 Dec;261(6 Pt 1):E782-8. doi: 10.1152/ajpendo.1991.261.6.E782.


We examined GLUT-4 glucose transporter protein and mRNA in muscle tissue from a new rodent model of non-insulin-dependent diabetes mellitus (NIDDM), the male obese Zucker diabetic fatty (ZDF) rat [ZDF/Drt-fa(F10)]. We also determined whether prevention of hyperglycemia might affect GLUT-4 expression by feeding the intestinal alpha-glucosidase inhibitor acarbose (40 mg/100 g diet) in the diet of male ZDF rats for 19 wk, starting at least 1 wk before the onset of diabetes. Fasting glucose was four- to sixfold greater in diabetic ZDF rats (24.1 +/- 6.7 mM) compared with lean or obese nondiabetic rats. Fasting insulin in diabetic ZDF rats (0.5 +/- 0.1 ng/ml) was similar to lean rats (0.4 +/- 0.1) but greatly reduced compared with obese nondiabetic rats (18.7 +/- 4.0 ng/ml). Acarbose treatment significantly reduced fasting glucose levels to 13.4 +/- 1.4 mM, while insulin levels increased to 1.6 +/- 0.3 ng/ml. GLUT-4 protein levels in diabetic ZDF rats were reduced approximately 40% in red quadriceps and mixed gastrocnemius muscles but were unchanged in white quadriceps muscle. Acarbose treatment was associated with a twofold increase in GLUT-4 protein and mRNA in mixed gastrocnemius muscle. These data indicate that, in this obese model of NIDDM without hyperinsulinemia, there is reduced muscle GLUT-4 protein in red but not white muscle fiber types. The decrease in muscle GLUT-4 expression in this model of NIDDM can be prevented by acarbose treatment, which reduces hyperglycemia and increases beta-cell responsiveness.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acarbose
  • Animals
  • Blood Glucose / metabolism
  • Blotting, Western
  • Body Weight
  • Diabetes Mellitus, Experimental / metabolism*
  • Down-Regulation
  • Gene Expression Regulation
  • Hypoglycemic Agents / pharmacology
  • Male
  • Monosaccharide Transport Proteins / genetics
  • Monosaccharide Transport Proteins / metabolism*
  • Muscles / metabolism*
  • Obesity / metabolism
  • Rats
  • Rats, Zucker
  • Trisaccharides / pharmacology


  • Blood Glucose
  • Hypoglycemic Agents
  • Monosaccharide Transport Proteins
  • Trisaccharides
  • Acarbose