The polyol pathway and osmoregulation in js1 schwann cells grown in hyperglycemic and hyperosmotic conditions. Mizisin, Andrew P., Li Li, Michelle Perello, Jason D. Freshwater, Michael W. Kalichman, Linda Roux, and Nigel A. Calcutt. Veterans Administration Medical Center and the Department of Pathology (Neuropathology), School of Medicine, University of California, San Diego, La Jolla, California
APStracts 2:0115F, 1995.
To test the osmoregulatory roles of Schwann cell aldose reductase and myo-inositol, JS1 Schwann cells were grown under control and hyperosmotic conditions with and without excess glucose or galactose. JS1 cells cultured in control conditions possessed aldose reductase protein and activity that was not altered by the inclusion of 25 mM glucose or galactose. Following culture with 100 mM NaCl, there was a decline in cell number accompanied by an increase in aldose reductase activity both of which were attenuated by the addition of 25 mM glucose or galactose. Sorbitol was not detected in JS1 Schwann cells following culture in control, glucose-supplemented or hyperosmotic medium, and dulcitol accumulated only following culture with galactose. However, both polyols were dramatically increased in JS1 cells cultured in hyperosmotic medium supplemented with 25 mM glucose or galactose. In contrast, myo-inositol levels were elevated only during hyperosmotic exposure but decreased when glucose or galactose were also present. These data are consistent with the use of polyol formation by JS1 Schwann cells as a means of responding to osmotic stress.

Received 24 February 1995; accepted in final form 10 July 1995.
APS Manuscript Number F65-5.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 18 July 1995.