Partial reversal of asymmetry in microvessel neurochemical changes after ischemia by corpus callosum section.

Abstract

Common carotid occlusion in the rat significantly decreases the density of ,-adrenergic receptors in preparations of microvessels obtained from ipsilateral and contralateral cerebral cortices.

Aging modifies the asymmetry in brain microvascular regulation.

“…Although the basis of this phenomenon is at present unknown, for the interpretation of the data it is important to emphasize that these results are reminiscent of those previously obtained in split-brain rats. 5 Along this line, the lack of effect of right carotid artery occlusion on the left hemisphere in aged rats suggests an impairment of the transfer of neuronal information to the contralateral side of the brain. Furthermore, the fact that the effect of left carotid artery ligature was also greatly attenuated in the ipsilateral hemisphere leads to the hypothesis that mechanisms regulating microvessel response to ischemia, which in adults seems to be exerted in an asymmetric manner showing a kind of polarity of the left side of the brain, depend on preserved neuronal integrity.…”

“…12 Recent studies of cerebral circulation have raised the hypothesis that cerebral lateralization may be exerted also at the level of neuronal mechanisms regulating microvessel function. 3 " 5 A large amount of experimental data suggests the existence of a functional adrenergic innervation of brain capillaries. 6 "" The relation between vascular function and neuronal activity seems to be mediated by adrenergic receptors located on cerebral capillaries.…”

Hippocampal and Cerebellar β‐Adrenergic Receptors and Adenylate Cyclase Are Differentially Altered by Chronic Ethanol Ingestion

“…Hippocampus contains the lowest concentration of &adrenergic receptors in the whole brain (Minneman et al, 1981). It has been proposed that the BI-adrenergic receptors may be localized neuronally (Minneman et al, 1981), whereas the P2-adrenergic receptors may be primarily nonneuronal, e.g., glial (Voisin et al, 1987) or vascular (Minneman et al, 1981;Magnoni et al, 1986), or at least localized extrasynaptically (Wilfert et al, 1982). Furthermore, autoradiographic studies of Sutin and Minneman (1985) failed to localize ICYP binding sites to any specific neuronal cell in the cerebellar cortex.…”