Regional net uptake of 14C-glucose by rat brain under the influence of corticosterone

Fifteen seconds after intracarotid injection of either 14C-glucose or tritiated water in adrenalectomized rats, the net uptake of the respective tracer by 18 brain regions and by the anterior pituitary was measured. Corticosterone added to the injection solution (1 or 100 micrograms ml-1; 0.2 ml per animal) caused a dose-dependent decrease of net uptake of 14C-glucose in twelve regions. Compared to the net uptake of tritiated water which was used as a measure of relative blood flow, it suggests that this effect, at least partially, is due to a decreased blood-brain barrier permeability to 14C-glucose. Furthermore, the regional net uptake of 14C-glucose was estimated in rats with different endogenous corticosterone levels but injected with an identical solution in each case. Statistically significant differences could be observed between adrenalectomized and restrained animals in three brain regions.