Memon, Riaz A., John Fuller, Arthur H. Moser, Kenneth R. Feingold, and Carl Grunfeld. In vivo regulation of plasma platelet-activating factor acetylhydrolase during the acute phase response. Am. J. Physiol. 277 (Regulatory Integrative Comp. Physiol. 46): R94–R103, 1999.—Plasma plateletactivating factor acetylhydrolase (PAF-AH) hydrolyzes PAF and oxidized phospholipids and is associated with lip...

PURPOSE Platelet-activating factor (PAF), a phospholipid mediator of inflammation, has been recently detected on tumor cells but its effect in tumor development is largely undefined. EXPERIMENTAL DESIGN To address its potential role in tumor biology, we inhibited intratumor PAF activity by engineering tumor cell lines to express plasma PAF-acetylhydrolase (PAF-AH), the major PAF-inactivating ...

The phospholipid mediator platelet-activating factor (PAF) increased the release of prostaglandin E (PGE ) from astrocyte-enriched 2 2 cortical cell cultures in a concentrationand time-dependent manner. The nonhydrolyzable PAF analog methylcarbamyl-PAF (mc-PAF), the PAF intermediate lyso-PAF, and arachidonic acid (AA) also produced this effect. In contrast, phosphatidlycholine (PC) and lyso-PC,...

A competitive PCR assay was developed to quantify platelet-activating factor (PAF) receptor (PAF-R) transcripts in rat tissues using a synthetic RNA as a competitor. We found PAF-R mRNA constitutively expressed in the eight organs tested, with the ileum containing the highest concentration [(3.49+/-0.15) x 10(7) molecules/microg of RNA]. Significant but lower levels were also detected in the je...

tory conditions of the gingival and underlying bone and connective tissue. Platelet-activating factor (PAF), a potent inflammatory phospholipid mediator that has been previously detected in elevated levels in inflamed gingival tissues, in gingival crevicular fluid and in saliva, is implicated in periodontal disease. Our results from previous studies showed that the biologically active phospholi...

Platelet-activating factor (PAF), the potent phospholipid mediator of inflammation, is involved in atherosclerosis. Platelet-activating factor-acetylhydrolase (PAF-AH), the enzyme that inactivates PAF bioactivity, possesses both acetylhydrolase and transacetylase activities. In the present study, we measured acetylhydrolase and transacetylase activities in human atherogenic aorta and nonatherog...

This study investigated the direct and indirect effects of platelet activating factor (PAF, PAF-acether) on human isolated airways. PAF caused a single non-repeatable contraction which was found to be variable both between lung samples and within tissues from the same lung. The range of contractions induced by PAF, 7 X 10(-8), M and 7 X 10(-7) M was 2-55% and 3-72% of the maximal response to ca...

Platelet-activating factor (PAF) may be a mediator of some sequelae of cholecystitis, a disorder with gallbladder motor dysfunction. The aims of this study were to determine the effect and mechanism of PAF on gallbladder muscle. Exogenous administration of PAF-16 or PAF-18 caused dose-dependent contractions of gallbladder muscle strips in vitro with threshold doses of 1 ng/ml and 10 ng/ml, resp...

Rationale: The phospholipid platelet-activating factor (PAF) stimulates all cells of the innate immune system and numerous cardiovascular cells. A single enzyme (plasma PAF acetylhydrolase [PAF-AH] or lipoproteinassociated phospholipase [Lp-PL]A2) in plasma hydrolyzes PAF, but significant controversy exists whether its action is proor antiinflammatory and accordingly whether its inhibition will...

Controversy exists as to whether platelet-activating factor (PAF), a potent phospholipid mediator of inflammation, can actually protect the heart from postischemic injury. To determine whether endogenous activation of the PAF receptor is cardioprotective, we examined postischemic functional recovery in isolated hearts from wild-type and PAF receptor-knockout mice. Postischemic function was redu...