AJP - Regulatory, Integrative and Comparative Physiology, Vol 248, Issue 4 447-R452, Copyright © 1985 by American Physiological Society
Level of satiety: fatty acid and glucose metabolism in three brain sites associated with feeding
T. R. Kasser, R. B. Harris and R. J. Martin
Two experiments were conducted to determine if the level of satiety alters
fatty acid and glucose metabolism in selected brain areas. Rats received
150, 100, or 50% of normal intake by gastric intubation for 7 days. Thus
the impetus for spontaneous feeding would be impaired in 150% fed rats
(anoretic), potentiated in 50% fed rats (hungry), and maintained in 100%
fed (control) rats. In vitro metabolism of glucose and palmitate was
examined in liver, cortex, ventrolateral hypothalamus (VLH), ventromedial
hypothalamus (VMH), and area postrema nucleus of the solitary tract. The
VLH of hungry (50%) rats had a 40% increase in palmitate oxidation and a 9%
decrease in glucose oxidation compared with controls (100%). The VLH of
anoretic rats (150%) had a 36% decrease in palmitate oxidation and a 20%
increase in glucose oxidation compared with controls. Hepatic metabolic
differences were similar to those seen in VLH. Total fatty acid synthesis
was 37% higher in anoretic and 29% lower in hungry compared with control
rats. Recognition of excess, sufficient, or deficient peripheral energy
status may be a process that monitors both VLH energy utilization and VMH
energy storage in an attempt to depict metabolic adaptations of the
periphery.
