Topographic and laminar maturation of striate cortex in early postnatal marmoset monkeys, as revealed by neurofilament immunohistochemistry.
The maturation of pyramidal neurons in the primary visual cortex (V1) of marmoset monkeys was investigated using an antibody (SMI-32) to non-phosphorylated neurofilament protein (NNF). Analysis of animals aged between birth and postnatal day 91 (PD 91, which corresponds approximately to the peak of synaptogenesis in this species) revealed discrete changes in both the laminar and the areal distribution of NNF. At PD 0, the upper part of layer 6 contained darkly labelled neurons and associated neuropil, including axons. In this layer a centroperipheral gradient, with more labelled cells in the foveal representation, was apparent at PD 0. This topographic gradient gradually disappeared, and by PD 91 a similar density of labelled layer 6 cells was observed throughout V1. Labelled cells were not apparent in layer 3C until PD 7, and were not distributed according to a topographic gradient. Labelled cells were first observed in layer 3B(alpha) at PD 28, when they formed a centroperipheral gradient similar to that seen in layer 6. This gradient was still evident in an adult animal. These results demonstrate an inside-out profile of postnatal cortical development, with the topographic pattern of maturation of V1 mimicking the centroperipheral gradient of maturation in the retina.
Bourne
James A
JA
Department of Physiology and Monash University Centre for Brain and Behaviour, Monash University, Victoria 3800, Australia. james.bourne@med.monash.edu.au
Warner
Claire E
CE
Rosa
Marcello G P
MG
D000818:Animals; D000831:Animals, Newborn; D000906:Antibodies; D002144:Callithrix; D007150:Immunohistochemistry; D016900:Neurofilament Proteins / Q000276:immunology / Q000378:metabolism*; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D013569:Synapses / Q000502:physiology; D014793:Visual Cortex / Q000166:cytology* / Q000254:growth & development*
D000906:Antibodies; D016900:Neurofilament Proteins