Differentiating effects of murine nerve growth factor in the peripheral and central nervous systems of Xenopus laevis tadpoles.

The present investigation was directed toward exploration of the spectrum of action of murine nerve growth factor (m-NGF) in peripheral cells and neurons in the central nervous system (CNS) of Xenopus laevis tadpoles. It was found that systemic m-NGF injections elicit growth and differentiative effects not only on sensory and sympathetic nerve cells but also on several populations in the CNS. The finding that aminergic and peptidergic neurons in brain centers are highly receptive to m-NGF activity provides evidence for the broad spectrum of action of this molecule in lower vertebrates and calls for a systematic search for these and other putative target cells in the CNS of higher vertebrates.