Dark-rearing fails to affect the basal dendritic fields of layer 3 pyramidal cells in the kitten's visual cortex.
The development of the cat's visual cortex is incomplete at birth and is influenced by the cat's early visual experience. We have previously demonstrated that the basal dendritic fields of layer 3 pyramidal cells grow substantially during the first 5 weeks after birth and that stripe-rearing affects their orientation. In this paper we determined the effects on these dendritic fields of visual deprivation (dark-rearing) during the first 3 months of life. The visual cortices of both normally reared and dark-reared cats were impregnated by the Golgi method, sectioned in the tangential plane and counterstained. The basal dendritic fields of completely impregnated pyramidal cells from layer 3 were drawn with the aid of a camera lucida, and compared in terms of number and length of primary dendrites, branching, size, elongation, and distribution of dendritic field orientations. Surprisingly, we observed no significant differences in any parameter measured. Thus, although stripe-rearing can specifically alter the orientation of the dendritic fields of the layer 3 pyramidal cells, and dark-rearing has been shown by others to alter the size of layer 4 stellate cells, dark-rearing failed to affect the dendritic fields of layer 3 pyramidal cells.
Tieman
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SB
Neurobiology Research Center, State University of New York, Albany 12222, USA.
Zec
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Tieman
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DG
D000818:Animals; D002415:Cats; D002452:Cell Count; D003712:Dendrites / Q000502:physiology*; D015509:Developmental Biology; D009474:Neurons / Q000502:physiology; D017966:Pyramidal Cells / Q000166:cytology* / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology*