Stem cell factor alters membrane potential of purified peritoneal mast cells in culture. Wang, Yu Hua, Vay Liang W. Go, S. Vincent Wu, and Jen Yu Wei. Dept. of Med. & Brain Res. Inst., School of Medicine, and CURE: Digestive Diseases Res. Ctr., VA Wadsworth Med. Ctr., UCLA, Los Angeles, CA 90095, USA
APStracts 3:0352C, 1996.
The membrane potential (Em) was used as an indicator to evaluate the effect of stem cell factor (SCF) on the membrane integrity of peritoneal mast cells (PMCs). PMCs were harvested from the peritoneal lavage of Sprague-Dawley rats, purified more than 95% and cultured with or without the presence of SCF (2 X 10-8 M). Ems were measured with conventional intracellular recording techniques. Results from day 1 to day 4 in culture were compared. Significant differences in average Ems (aEms) (p< 0.01, ANOVA) were seen on days 3 and 4; -67.4 +/- 8.0 & -59.4 +/- 4.8 mV with SCF vs -24.8 +/- 7.9 & -7.6 +/- 3.9 mV without SCF (mean +/- SEM mV), respectively. Moreover, after in culture with SCF more than one week, the aEms of purified PMCs tend to reach a plateau values similar to that of unpurified PMCs on day 1 (at -20's mV). The morphological appearances of PMCs can be correlated with the results of aEms measurements. PMCs with a smooth spherical shape and highly refractive appearance, and better tolerance to electrode impalement, showed Ems with greater negative values and lesser fluctuations. These results indicate that SCF can maintain the membrane properties and viability of purified PMCs in a long-term culture.

Received 16 May 1996; accepted in final form 3 October 1996.
APS Manuscript Number C269-6.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 13 November 1996