Regional glucose metabolism in the rabbit brain in control and TRH-treated animals

The local cerebral metabolism in urethane anaesthetized control and TRH-treated rabbits was studied with the [14C]2-deoxyglucose method. In the controls, the glucose use was found to be highest in regions known to have a high blood flow and low in regions with low flow. The glucose consumption was, calculated using the constants found by Kennedy et al. in monkeys, 23.5 +/- 6.0 mumol 100 g-1 min-1 in parietal cortex. The TRH was infused at a dose of 0.06 mg kg-1 min-1 which is known to cause vasodilation in the brain. No marked influence of the peptide on the glucose use was detected. It was concluded that the previously reported cerebral vasodilation caused by TRH is not due to an increase in cerebral metabolism.