AJP - Regulatory, Integrative and Comparative Physiology, Vol 239, Issue 3 344-R351, Copyright © 1980 by American Physiological Society
Evidence for a circulating ergostatic factor: studies on parabiotic rats
Y. Nishizawa and G. A. Bray
The effect of electrolytic ventromedial hypothalamic lesions or forced
overfeeding through gastric cannulas was studied in parabiotic rats. In one
experiment a ventromedial hypothalamic lesion in one member of the
parabiotic union was associated with an increased fatness in the lesioned
rat and a decrease in fat pad weight and a rise in body density (loss of
fat) of the unlesioned animal. In the other two experiments a high fat or
high carbohydrate diet was tube fed to one member of a parabiotic union.
The average preinfusion intake per rat was 56 kcal/day. When 90 kcal/day
were given through the intragastric cannula, oral intake of calories for
the two animals fell to approximately 44 kcal/day. Body fat of the
non-tube-fed animal was less than in the tube-fed controls. These studies
suggest the presence of an ergostatic (energy stabilizing) factor that
enters and is transported in the blood with passage from one animal to
another.
