The effect of pretreatment with pentobarbital on the extent of [14C] incorporation from [U-14C]glucose into various rat brain glycolytic intermediates: relevance to regulation at hexokinase and phosphofrucktokinase |
| |
Authors: | L P Miller S Mayer L D Braun P Geiger W H Oldendorf |
| |
Institution: | (1) Brentwood Division 151C, Research Service, West Los Argeles VA Medical Center, 11301 Wilshire Blvd., 90073 Los Angeles, California;(2) Department of Neurology, UCLA School of Medicine, 90042 Los Angeles, California;(3) Department of Pharmacology, University of Southern California, 90033 Los Angeles, California;(4) Present address: Neuroscience Laboratory, 151S Rm GE203, Vet Adm. Med. CTR, 50 Irving St. NW, 20422 Washington, D.C. |
| |
Abstract: | In the present investigation we monitored the incorporation of 14C] from U-14C]glucose into various rat brain glycolytic intermediates of conscious and pentobarbital-anesthetized animals. Labeled glucose was delivered to brain by single bolus intracarotid injection and brain tissue was subsequently prepared at 15, 30 and 45 sec by freeze-blowing. Glycolytic intermediates were then separated by column chromatography. Our results showed a gradual decrease with time of14C-labeled glucose which gave a calculated rate for glucose metabolism of 0.86 mol/min/g and 0.56 mol/min/g in conscious and anesthetized animals, respectively. Compared to the results obtained using conscious animals the administration of pentobarbital not only resulted in a significant attenuation of the rate of glucose metabolism but also caused a similar reduction in the amount of14C incorporated into several glycolytic intermediates. These intermediates included: glucose 6-phosphate, fructose 6-phosphate, fructose, 1,6 diphosphate, dihydroxyacetone phosphate and post glycolytic compounds. In addition, pretreatment with pentobarbital resulted in a 75% increase in the endogenous concentration of glucose, 10% increase in glucose 6-phosphate, no change in fructose 6-phosphate and 42% decrease in lactate compared to levels in brains obtained from conscious animals. These results are discussed in relation to control of glycolysis through coupled regulation at hexokinase-phosphofructokinase. |
| |
Keywords: | Rat brain glycolysis regulation pentobarbital |
本文献已被 SpringerLink 等数据库收录! |
|