skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Hypothalamic norepinephrine turnover response to a single low protein, high carbohydrate meal in the male Wistar rat

Conference · · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)
OSTI ID:5321971

A single meal stimulates norepinephrine turnover (NET) by approximately 4-fold in the brown adipose tissue (BAT). In this experiment the role of the hypothalamus in regulating this response was examined. NET was measured in the cortex (C), ventro-medial (VMH), and the lateral hypothalamus (LH). A total of 48 male Wistar rats (200 g body weight) were trained to eat during two feeding sessions per day. On the experimental day, one group (N = 24) was meal deprived and the other (N = 24) was given a low protein, high carbohydrate test meal for 2 hours. NET was determined by the synthesis inhibition method using alpha-methyltyrosine (AMT) injected within one hour after the meal. Norepinephrine (NE) content in each brain section was measured by radioimmunoassay at 4 time points (0, 1, 2, 3 hours) after AMT. The turnover rate (TR) was calculated as the slope of the decline in NE content over time (ng/mg protein/hr) following AMT. The fraction of the total pool of NE released/hr (k) was calculated by dividing the slope (TR) by the Y intercept (NE content at zero time). NET (TR) increased significantly (p < .05) in the VMH following a meal (9.36 +/- .67 vs 8.04 +/- .98 ng/hr; fed vs deprived). There was no change in TR in the C or LH, or in k in any brain section. The marked (4-fold) increase in BAT NET and minimal increase in VMH NET suggests that the meal has a direct effect on BAT with the VMH playing a secondary or modulatory role.

Research Organization:
UCLA Medical Center, Torrance
OSTI ID:
5321971
Report Number(s):
CONF-8604222-; TRN: 86-028382
Journal Information:
Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:3; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
Country of Publication:
United States
Language:
English