J. Biol. Chem., Vol. 262, Issue 2, 527-530, 01, 1987

Occurrence of an endogenous inhibitor of platelet-activating factor in rat liver

M Miwa, C Hill, R Kumar, J Sugatani, MS Olson and DJ Hanahan

Hepatocytes obtained from livers derived from fed rats perfused with a collagenase-containing mixture were found to contain significant levels of platelet-activating factor activity as isolated by Silica Gel G thin layer chromatography. However, when soybean trypsin inhibitor was included in the collagenase-containing perfusion medium for hepatocyte preparation, platelet-activating factor activity could not be detected on Silica Gel G chromatograms. Examination of the lipids extracted from freeze clamped perfused rat livers revealed low, but detectable, levels of platelet-activating factor. Further investigation of these observations indicated that a lipid-like inhibitor was present in freeze-clamped perfused livers as well as in hepatocytes isolated in the presence of soybean trypsin inhibitor. In each instance platelet- activating factor and this newly discovered inhibitor, which comigrated at the same RF value on Silica Gel G thin layer chromatography plates, could be separated by further chromatography on high performance thin layer plates. The present study shows that platelet-activating factor is present in unstimulated liver and that its detection is masked by an endogenous lipid-like inhibitor.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				T. A. Hinterleitner, J. D. Valentich, J.-H. Cha, P. Will, A. Welton, and D. W. Powell J. Pharmacol. Exp. Ther., June 1, 1997; 281(3): 1264 - 1271. [Abstract] [Full Text]