Estradiol enhances brain glucose uptake in ovariectomized rats

Abstract

This study was designed to investigate the effects of 17β-estradiol benzoate (E 2B) on brain glucose uptake and transport across the blood-brain barrier (BBB). Both a time- and dose-response evaluation of the effect of E 2B on glucose uptake in the central nervous system (CNS) were conducted. E 2B, in doses ranging from 1 to 100 μg/kg body weight, was injected subcutaneousy at 2 to 24 h prior to evaluation. The 4h time point and 10 μg/kg dose of E213 produced the most widespread increases in glucose uptake. Six regions responded to E213 with elevated glucose uptake by as much as 120% when compared to oil-treated controls. We then evaluated the effects of E213 on transport of glucose across the BBB. E 2B significantly increased the extraction of labeled sugar across the BBB by 40% without affecting extraction of the internal standard. Collectlvey, these studies indicate that physiological levels of estradiol (E 2) may play an important role in modulating cerebral glucose homeostasis.