Cerebrovascular evidence for a GABAergic modulation of the cholinergic vasodilatatory basalocortical system in the rat

The present work is aimed to study the functional relevance of GABAergic-ch olinergic interactions on the modulation of cerebral blood flow (CBF) exert ed by the basalocortical system. Injections of GABA into the substantia inn ominata (SI) induce increases in blood flow in several cortical areas and i nhibit partly the increases in cortical blood flow induced by cholinergic a ctivation of this structure. Blockade of local GABAergic receptors by picro toxin induced almost similar effects. These findings suggest that local GAB Aergic neurones of the SI exert a complex cortical cerebrovascular modulati on at a resting and an activated state. (C) 1999 Elsevier Science B.V. All rights reserved.