Development of visual callosal connections in neonatally enucleated rats.

摘要: The present report extends previous descriptions of the mature distributions callosal cells and axonal terminations in rats monocularly or binocularly enucleated at birth. It also describes time course development these animals, establishes age which eye removal ceases to alter normal development. Although our results indicate that pattern is anomalous adult, neonatally rats, major features are nonetheless clearly recognizable both rats. Thus, as normally reared there dense accumulations 17/18a border region, lateral area 18a, within 18b In addition, several narrow bands connections bridge width 18a rostrocaudal levels, a ring-like configuration located anterolateral 17. In most prominent anomaly develops hemisphere ipsilateral remaining eye, where band runs rostrocaudally through center 17. Periodic fluctuations density labeling along length this extra give it beaded appearance. contralateral appears normal. Binocular enucleation causes appearance discrete regions reduced densely labeled tongue-like extend medially from well into laminar distribution not significantly altered by loss one eyes birth. Our data does affect development. pups, all can be recognized 6–7 days age, 12 patterns appear virtually mature. Finally, reveal monocular binocular enucleations performed 6 later allow develop normally, whereas between birth 5 produce anomalies similar those observed about age—just earliest become discernible, long before first open their eyes—the developing pathway no longer susceptible disruptions visual input.