[Effects of 6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone on rabbit platelet aggregation and TXB2, cAMP production].

ABSTRACT

6-(alpha alpha-diphenylacetylpiperazinyl) phenyl-5-methyl-4,5-dihydro-3 (2H)-pyridazinone (DMDP) is a new synthetic pyridazinone derivative. This compound was shown to inhibit AA, ADP and PAF-induced rabbit platelet aggregation, and its IC50s were found to be 1.12 +/- 0.1, 4.19 +/- 0.5 and 2.97 +/- 0.1 mumol/L, respectively. At the concentration range of 1-500 mumol/L, the compound was found to depress TXB2 content and to increase cAMP levels in washed rabbit platelets in a dose-dependent manner. These might be the mechanisms of the compound on the inhibition of rabbit platelets.