Postnatal histogenesis and proliferation of cells of the parietal neocortex in normal mice and after brain trauma

The postnatal histogenesis of the parietal region of the neocortex and the ability of the principal cell types in it to proliferate were studied in normal mice and after a stab wound of the brain by analysis of cells labeled with [³H]thymidine in semithin sections. In the postnatal period no microneurons were formed in the parietal cortex of the mice either by migration of undifferentiated cells or by proliferation. Trauma to the right hemisphere caused no change in the direction of the histogenetic transformations of cells migrating into the parietal cortex toward their differentiation into microneurons.Laboratories of Brain Ultrastructure, Brain Cytoarchitectonics, and Functional Synaptology, Brain Institute, Academy of Medical Sciences of the USSR, Moscow. Central Research Laboratory, Patrice Lumumba Peoples' Friendship University, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 234–237, February, 1978.