The medullary cerebrovascular vasodilator area mediates cerebrovascular vasodilation and electroencephalogram synchronization elicited from cerebellar fastigial nucleus in Sprague-Dawley rats

We investigated whether the medullary cerebrovasodilator area (MCVA), a reg ion of ventral medulla mediating elevations of regional cerebral blood flow (rCBF) and electroencephalogram (EEG) synchronization elicited in cerebral cortex from stimulation of reticulospinal neurons of rostral ventrolateral medulla (RVLM), also mediates comparable responses from the cerebellar fas tigial nucleus (FN). In spinalized rats, electrical stimulation of MCVA, RV LM or FN elevated rCBF and synchronized the EEG. The FN-evoked responses we re significantly attenuated or blocked by bilateral lesions of MCVA. The MC VA is a novel region of medullary reticular formation mediating actions of medullary and cerebellar centers on rCBF and EEG to link visceral centers o f brainstem and cerebral cortex. (C) 2000 Published by Elsevier Science Ire land Ltd.