Regional effect of mepyramine on cerebral glucose utilization in conscious rats

We examined effects of the antihistamine, mepyramine, which occupies cerebral H1-receptors, on regional brain metabolism of glucose in conscious rats. Although glucose utilization by most structures was not significantly affected, in high doses, mepyramine did cause modest, localized reductions in brain areas with both high (ventromedial nucleus of hypothalamus) and low (medial forebrain bundle) densities of histamine H1-receptors.