Neurogenic control of parenchymal arterioles in the cerebral cortex.

Abstract

Central neural vasomotor mechanisms act on the parenchymal vasculature of the brain to regulate regional cerebral blood flow (rCBF). Among the diverse components of the local neural circuits of the cerebral cortex, many may contribute to the regulation of rCBF. For example, the cholinergic vasodilative system that originates in the basal forebrain acts on the neocortex and hippocampus. Notably, rCBF is reduced in the elderly and patients with dementia. The vasodilatory response, independent of changes in blood pressure and glucose metabolism in the brain, occurs in the parenchymal arterioles to produce a significant increase in cortical rCBF. Recent studies illuminate the physiological role of the cholinergic vasodilator system related to neurovascular coupling, neuroprotection, and promotion of the secretion of nerve growth factor. In this review, cellular mechanisms and species differences in the neurogenic control of vascular systems, as well as benefits of the cholinergic vasodilatory systems against cerebral ischemia- and age-dependent impairment of neurovascular plasticity, are further discussed.