AJP - Endocrinology and Metabolism, Vol 252, Issue 4 E461-E466, Copyright © 1987 by American Physiological Society
Deprivation of corticosterone does not prevent onset of obesity in Zucker fa/fa pups
R. Bazin, E. Planche, F. Dupuy, S. Krief and M. Lavau
Adrenalectomy has been shown to reduce the development of obesity in adult
Zucker fatty rat. In this study, we examined whether adrenalectomy could
prevent the emergence of obesity and correct any of the first abnormalities
to develop in fa/fa pups. Four-day-old Zucker pups were adrenalectomized
and fed by adrenalectomized wet nurses until 11 days of age. The frequency
distribution curves of fat cell volume clustered in two groups as they do
in control litters, providing evidence that two phenotypes were present.
Oxygen consumption measured at 8 days of age was significantly lower in
fa/fa than in Fa/fa. Adrenalectomy did not restore the decreased oxygen
consumption of fa/fa. In control litters, the GDP binding to brown adipose
tissue mitochondria was twofold lower, whereas fatty acid synthase activity
of this tissue was significantly increased in fa/fa pups. In inguinal
adipose tissue of fa/fa pups, fatty acid synthase, and lipoprotein lipase
activities were twice as active as in the tissue of lean pups. In
adrenalectomized fa/fa pups, none of these metabolic abnormalities was
corrected. The results demonstrate that adrenalectomy early in life did not
prevent the emergence of obesity in suckling fa/fa rats.
