Hypothalamic regulatory peptides in obese and lean Zucker rats.
1. Hypothalamic concentrations of nine peptides with experimental effects on energy balance were compared in obese (fa/fa) and lean (Fa/?) male Zucker rats. To determine whether any peptide differences between obese and lean rats might be due to the overweight condition per se, separate groups of obese rats were food-restricted to reduce their body weight to lean values. 2. Concentrations of neuromedin B, a bombesin-like peptide, in the central hypothalamus were significantly higher in obese than in lean rats. This difference was not affected in food-restricted obese rats. 3. Hypothalamic levels of neuropeptide Y, an extremely potent central appetite stimulant, were similar in lean and freely fed obese rats but central hypothalamic levels of neuropeptide Y rose significantly in food-restricted obese rats. 4. These findings suggest that disturbances in hypothalamic neuromedin B concentrations may be involved in the obesity syndrome of the fa/fa Zucker rat. Increased central hypothalamic levels of neuropeptide Y in food-restricted rats suggest that this peptide may help to defend body weight by stimulating eating after weight loss.
Williams
G
G
Francis Fraser Laboratories, Royal Postgraduate Medical School, London, U.K.
Cardoso
H M
HM
Lee
Y C
YC
Ball
J M
JM
Ghatei
M A
MA
Stock
M J
MJ
Bloom
S R
SR
D000818:Animals; D001839:Bombesin / Q000032:analysis; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis; D005508:Food Deprivation; D019004:Galanin; D007031:Hypothalamus / Q000737:chemistry*; D007033:Hypothalamus, Middle / Q000737:chemistry; D015287:Neurokinin B / Q000031:analogs & derivatives / Q000032:analysis; D009478:Neuropeptide Y / Q000032:analysis; D009479:Neuropeptides / Q000032:analysis*; D009496:Neurotensin / Q000032:analysis; D009765:Obesity / Q000378:metabolism*; D010455:Peptides / Q000032:analysis; D011863:Radioimmunoassay; D051381:Rats; D011924:Rats, Zucker; D013004:Somatostatin / Q000032:analysis; D013373:Substance P / Q000032:analysis; D014660:Vasoactive Intestinal Peptide / Q000032:analysis
D009478:Neuropeptide Y; D009479:Neuropeptides; D010455:Peptides; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D009496:Neurotensin; D013004:Somatostatin; D015287:Neurokinin B; C038393:neuromedin B; D019004:Galanin; D015740:Calcitonin Gene-Related Peptide; D001839:Bombesin