Gastric inhibitory polypeptide release from a tumor derived cell line. Kieffer, Timothy J., Zhongxian Huang, Christopher H. S. McIntosh, Alison M. J. Buchan, John C. Brown, and Raymond A. Pederson. Department of Physiology, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
APStracts 2:0060E, 1995.
A cell line derived from intestinal tumors of transgenic mice (STC-1) was sub-cloned to produce a stable line with approximately 30% immunoreactive gastric inhibitory polypeptide (IRGIP) containing cells (STC 6-14). HPLC of STC 6-14 extracts indicated that the tumor cell derived IRGIP had the same retention time as synthetic porcine GIP(1-42) (pGIP). Approximately 30% of the cells also contained immunoreactive somatostatin (IRSS) which eluted as a single peak on HPLC, corresponding with SS(1-14). On average, each well of extracted cells (5.0 x 105 cultured 4 days) contained 33.3 +/- 1.4 ng IRGIP and 18.4 +/- 1.5 ng IRSS. Basal release of IRGIP in the presence of 5 mM glucose was 733 +/- 58 pg/ml cells/2h (2.20 +/- 0.17 % of total cell content; TCC) and doubled at 20 mM glucose (4.20 +/- 0.42 %TCC). The response to glucose was augmented by addition of a SS neutralizing antibody (SOMA-10), and suppressed by 10 nM SS. Basal release of IRSS in 5mM glucose was 377 +/- 35 pg/ml cells/2h (2.05 +/- 0.19 %TCC) and was increased by glucose (>/=15 mM), and the addition of pGIP (>/= 1 nM). The STC 6-14 cell line represents a model to study the synthesis, storage and release of GIP and SS, in a controlled environment.

Received 29 June 1994; accepted in final form 23 March 1995.
APS Manuscript Number E234-4.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  4 April 1995.