Reduced glucose-induced neuronal activation in the hypothalamus of diet-induced obese rats

Brain Res. 1998 Oct 19;808(2):317-9. doi: 10.1016/s0006-8993(98)00839-7.

Abstract

Rats predisposed to develop diet-induced obesity (DIO) preferentially activate their sympathetic nervous system during intracarotid glucose infusion [B.E. Levin, Intracarotid glucose-induced norepinephrine response and the development of diet-induced obesity, Int. J. Obesity 16 (1992) 451-457.] but their brains are generally less responsive to glucose than diet-resistant rats (DR) [B.E. Levin, K.L. Brown, A.A. Dunn-Meynell, Differential effects of diet and obesity on high and low affinity sulfonylurea binding sites in the rat brain, Brain Res. 739 (1996) 293-300.; B.E. Levin, B. Planas, Defective glucoregulation of brain alpha2-adrenoceptors in obesity-prone rats, Am. J. Physiol. 264 (1993) R305-R311.; B.E. Levin, A.C. Sullivan, Glucose-induced norepinephrine levels and obesity resistance, Am. J. Physiol. 253 (1987) R475-R481.; B.E. Levin, A.C. Sullivan, Glucose-induced sympathetic activation in obesity-prone and resistant rats, Int. J. Obesity 13 (1989) 235-246.]. Here, 1 h intracarotid glucose infusions (4 mg/kg/min) selectively increased Fos-like immunoreactivity (FLIR) in the hypothalamic paraventricular, ventromedial, dorsomedial and arcuate nuclei of inbred DR but not DIO rats. This suggests that enhanced glucose-induced sympathetic activation in DIO rats is related to a failure of glucose to produce neuronal activation in these areas.

Publication types

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

MeSH terms

  • Animals
  • Arcuate Nucleus of Hypothalamus / cytology
  • Arcuate Nucleus of Hypothalamus / metabolism
  • Diet
  • Dorsomedial Hypothalamic Nucleus / cytology
  • Dorsomedial Hypothalamic Nucleus / metabolism
  • Glucose / pharmacology*
  • Hypothalamus / cytology
  • Hypothalamus / metabolism*
  • Neurons / chemistry
  • Neurons / drug effects*
  • Neurons / physiology*
  • Obesity / metabolism*
  • Paraventricular Hypothalamic Nucleus / cytology
  • Paraventricular Hypothalamic Nucleus / metabolism
  • Proto-Oncogene Proteins c-fos / analysis
  • Rats
  • Rats, Mutant Strains
  • Rats, Sprague-Dawley
  • Suprachiasmatic Nucleus / cytology
  • Suprachiasmatic Nucleus / metabolism
  • Supraoptic Nucleus / cytology
  • Supraoptic Nucleus / metabolism
  • Ventromedial Hypothalamic Nucleus / cytology
  • Ventromedial Hypothalamic Nucleus / metabolism

Substances

  • Proto-Oncogene Proteins c-fos
  • Glucose