Effects of synthetic analogues of platelet-activating factor (PAF) on fibrinolytic activity in the rat
Hofmann, B.; Meisgeier, U.; Kertscher, P.; Ostermann, G.
Biomedica Biochimica Acta 47(10-11): S161-S164
1988
ISSN/ISBN: 0232-766X PMID: 3150268 Document Number: 315298
PAF and structural analogues were investigated for their in vivo effects on fibrinolytic activity (FA) in the rat. The i.v. administration of 1 and 4 micrograms/kg PAF caused a dose-dependent increase in FA which was shown to be attributable to the release of tissue-type plasminogen activator (t-PA). 1-O-hexadecyl-2-O-ethyl-glycero-3-phosphoric acid-2'-N-propargyl-N,N'- dimethylammoniumethyl ester (I) and 1-O-hexadecyl-2-(n-propyl)-propanediol-3-phosphocholine (II) increased FA according to their proaggregatory activity. In contrast, 1-O-hexadecyl-2-O-ethyl-rac-glycero-3-phosphoric acid-5'-trimethylammoniumpentyl ester (III), a competitive antagonist of PAF, reduced the PAF induced increase of FA by 30%. Under identical conditions BN 52021 given at 1 and 10 micrograms/kg amounts diminished the effect of PAF by 47 and 77%, respectively. These results indicate that the PAF induced PA release in vivo is receptor mediated.