Nerve growth factor (ngf) synthesis by intestinal epithelial cells. Varilek, Gary W., Garry A. Neil, Warren P. Bishop, James Lin, and Nicholas J. Pantazis. Department of Internal Medicine, University of Kentucky College of Medicine, Lexington, KY. 40536, Gastrointestinal Research, Astra/Merck Group of Merck & Company, Wayne, PA. 19087, Department of Pediatrics, University of Iowa College of Medicine, Iowa City, IA. 52242, Department of Anatomy, University of Iowa College of Medicine, Iowa City, IA. 52242
APStracts 2:0065G, 1995.
Nerve growth factor (NGF) exists in the gut of adult rats. The cells responsible for NGF synthesis in the gut remain unknown. IEC-6 and Caco-2 cells, established cell culture models of intestinal epithelial cells, were studied to determine whether they synthesize and release NGF. Conditioned media from both IEC-6 and Caco-2 cells stimulated neurite outgrowth in both rat pheochromocytoma (PC12) cells and sensory neurons derived from embryonic chick dorsal root ganglia (DRG). The addition of anti-NGF antibody blocked neurite outgrowth in PC12 cells and partially blocked outgrowth in DRG cells. An NGF-ELISA readily detected immunoreactive NGF in conditioned media from both cell lines, while cellular extracts from IEC-6, Caco-2 and isolated rat intestinal epithelial cells had low levels of immunoreactivity. Caco-2 monolayers primarily secreted NGF from the basolateral compartment and interleukin-1 enhanced its secretion. IEC-6, Caco-2, and isolated rat intestinal epithelial cells expressed NGF-mRNA as determined by reverse transcription polymerase chain reaction. These observations suggest that intestinal epithelial cells are capable of NGF synthesis.

Received 22 August 1994; accepted in final form 13 March 1995.
APS Manuscript Number G313-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 19 April 1995.