Atsuhiro Onoda

Regulation by midbrain raphe nuclei and locus ceruleus on cerebral vasomotor responses

It has been suggested that midbrain raphe nuclei have important roles in cerebral circulation and metabolism [1-3] by sending serotonergic fibers to both the large and small vessels of the brain [4,5] as well as to the locus ceruleus [6,7], which is the center of the adrenergic system. However, few studies [8,9] have been reported with regard to the functional significance of the serotonergic system in cerebral vasomotor responses to changes in arterial CO 2 tension (PaCOp. Moreover, no study was undertaken regarding the cerebral vasomotor responses to changes in perfusion pressure. The focus of the present study was directed towards the roles of these nuclei in the cerebral vasomotor responses to changes in cerebral perfusion pressure and PaCOz.