Nerve Growth Factor (NGF) acutely enhances high-voltage activated Calcium currents in molluscan neurons. Wildering, Willem C., Johannes C. Lodder, Karel S. Kits and Andrew G.M. Bulloch. Neuroscience Research Group, Faculty of Medicine, University of Calgary, 3330 Hospital Drive, NW, Calgary, Alberta, Canada, T2N 4N1, Graduate School of Neurosciences Amsterdam, Research Institute Vrije Universiteit, Faculty of Biology, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands.
APStracts 2:0293N, 1995.
SUMMARY AND CONCLUSIONS
1. Nerve Growth Factor (NGF) is a member of a family of molecules (the neurotrophins) that can regulate the survival and/or outgrowth of many vertebrate cells. NGF also induces outgrowth from Lymnaea neurons under experimental conditions. Recent studies have shown that the neurotrophins can also acutely modulate some physiological properties of adult neurons. Here we examined the actions of NGF on high voltage-activated (HVA) Ca 2+ currents in Lymnaea motoneurons. 2. NGF induced a dose-dependent and reversible increase in HVA Ca 2+ currents within two minutes. 3- The threshold dose of the NGF- induced enhancement of HVA Ca 2+ currents ranged between 1 and 1000 pg/ml. In the most sensitive cells, the response saturated at doses higher than 1 ng/ml. 4- The results indicate that neurotrophins acutely modulate voltage-gated Ca 2+ currents in molluscan neurons through a high affinity signal transduction pathway. The data supports the existence of neurotrophins in invertebrates. Moreover, this property of NGF may explain the neuromodulatory actions of neurotrophins observed in various preparations.

Received 3 August 1995; accepted in final form 19 September 1995.
APS Manuscript Number J507-5.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 6 November 95