Repeated application of anodal direct current produces regional dominance in histamine-elicited cyclic AMP accumulation in rabbit cerebral cortex.

A unilateral 30-min application of anodal direct current to the promotor cortex of rabbits was repeated 10 times, and cyclic AMP accumulation in response to histamine was investigated in slices of different cortical areas. Polarization with 1.0 microA decreased the cyclic AMP accumulation in the cortical area contralateral to the polarization, by which regional dominance in cyclic AMP accumulation was produced in the polarized cortex. In contrast, the regional difference in cyclic AMP accumulation was reversed when 10.0 or 30.0 microA was applied. The histamine-elicited accumulation of cyclic AMP was almost completely inhibited by the selective H2-receptor antagonist cimetidine. These results suggest that repeated anodal polarization regionally alters H2-receptor-mediated cyclic AMP generation in the cortex depending on the intensity of the polarizing currents and this pattern of cyclic AMP accumulation is responsible for the characteristic motor behavior induced by anodal polarization.