A Morphological Study on the Microcirculation of the Central Nervous System. Selective Vulnerability to Hypoxia

We have examined the microvasculature of the human cerebral cortex, basal ganglia, hippocampus, cerebellar cortex and pons. In this presentation we summarize the results andy on the discuss the relationship between vasculature and the selectivere and its senile vulnerability of the brain to hypoxia. One of most characteristic features of the cerebral cortex is the presence of fountain‐like ramifications in the middle andn the deep cortical branches and the intracortical branches of theecure and its senile subcortical artery. The fountain‐like ramifications appeari as branches that originate from small arteries by repeated bifurcations occurring within short segments of the arteries. This particular structural blood vessel pattern of the corticalanese). gray matter is probably responsible for the ischemia that readily develops in generalized hypotension and may contributend cerbral to the development of pseudolaminar necrosis. Numerous reverse ramifications are present in the basal ganglia. It is thought that they play a significant role in bloodams JH, pressure regulation and occurrence of circulatory disturbances London, Mebone which are prone to involve these structures. Within the hippocampus, h 1 is supplied only by the sectora pathogenetic artery, whereas h 2 is nourished by the SA, DA, and DA 2 but h 2 is located at the most peripheral end of these branches. In addressing the question of the vulnerability of the hippocampalypoxamia, end plate it is evident that this cannot be accounted for by they WH, notion proposed by Lindenberg. Thus, the problem of vulnerability of h 1 and the end plate still remains to be explained by the vascular theory. The distribution of arteries in the cerebellar cortex closely resembles that of the cerebral cortex. There is no particular vascular distribution to the Purkinje cell layer, but this layerarchiture of has numerous arterial branches that are derived from the middle and deep cortical branches. The capillary networklar architure ofthe density is roughly equivalent to that of the molecular and granular layers. Hence it is not possible to readily account for the selective vulnerability of the Purkinje cells to hypoxia by the vascular distribution alone. Intertwinings of arterial branches particularly with formation of rope‐like structures are seen in fountain‐like ramifications. This type of configuration is observed in allshornerkrankung. regions examined and appear more frequently with advancing age, thus suggesting a certain correlation with the concomitant brain atrophy.