Expression of the transcription factor Zif268 in the visual cortex of monocularly deprived rats: Effects of nerve growth factor

Neurotrophins are known to be involved in experience-dependent plasticity o f the visual cortex. Here, we have characterized in detail the effects of i ntraventricular nerve growth factor infusion in monocularly deprived rats b y using immunostaining for the immediate-early gene product Zif268 as a mar ker of functional activity with cellular resolution. We have taken advantag e of the rapid regulation of Zif268 by visual input to reveal the cortical units that are responsive to the deprived eye after a period of monocular d eprivation. We found that responses to the deprived eye were significantly preserved in the cortex of monocularly deprived rats infused with nerve gro wth factor. The effects of nerve growth factor were greater for cortical ce lls located in deep layers and with more peripheral receptive fields. Resul ts from Zif268 staining correlated very well with those obtained by single- cell recordings from the visual cortex. Our results demonstrate that exogenous nerve growth factor preserves the fu nctional input from the deprived eye, enabling cortical neurons to activate immediate-early gene expression in response to stimulation of the deprived eye. Furthermore, we show that the intraventricular infusion of nerve grow th factor differentially affects the ocular dominance of cells at various d epths and eccentricities in the developing cortex. (C) 1999 IBRO. Published by Elsevier Science Ltd.