AJP - Regulatory, Integrative and Comparative Physiology, Vol 235, Issue 3 168-R174, Copyright © 1978 by American Physiological Society
Feeding responses of rats with dorsomedial hypothalamic lesions given ip 2DG or glucose
L. L. Bellinger, L. L. Bernardis and S. Brooks
The glucoprivation effects of 2-deoxy-D-glucose (2DG) on feeding behavior
were studied in rats with bilateral lesions of the dorsomedial hypothalamic
nucleus (DMN) and sham-operated controls. The lesioned and sham-operated
rats were injected intraperitoneally with 2DG (5% wt/vol) at doses of
either 150 mg/kg, 300 mg/kg, or 500 mg/kg, or with saline ("control days").
At all doses significantly more sham-operated rats ate and showed an
increased food consumption during the first few hours after 2DG injection
when compared to saline control days. However, their 24-h food consumption
was normal or less than normal, depending on the dose of 2DG. On the other
hand, rats with DMN lesions (DMN-L) did not increase their food consumption
during the 4 h after the injection at any of the 2DG doses. In a second
experiment DMN-L and sham-operated controls were injected intraperitoneally
with glucose (1.36 g/kg body wt or 2.72 g/kg body wt) or saline after an
overnight fast. Glucose loads, compared to saline injections, significantly
depressed the controls' food consumption only during the first hour of
refeeding. On the other hand, glucose injections did not depress food
intake of the DMN-L rats. It is suggested that DMN lesions may have either
destroyed glucoreceptors in the DMN that monitor glucose or the
glucoprivation effects caused by 2DG and/or glucoreceptive pathways that
pass through the DMN.
