Inhibitory effect of kaempferol against binding of platelet activating factor to its receptor / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>To observe the platelet activating factor (PAF) antagonistic effect of kaempferol.</p><p><b>METHOD</b>The specific binding of [3H] PAF to rabbit platelet receptor was investigatedwith radio ligand binding assay (RLBA). Platelet adhesion induced by PAF was measured with spectrophotometry. The elevation of inner free calcium concentration in rabbit polymorphonuclear leukocytes (PMNs) induced by PAF was determined with Fura-2 fluorescent technique.</p><p><b>RESULT</b>The 1, 2 or 4 nmol x L(-1) [3H]PAF specific binding to rabbit platelet receptor was inhibited by Kae dosage dependently and the IC50 were 30.8, 74.6 and 92.0 micro mol x L(-1), respectively. The PAF induced reactions of rabbit platelet adhesion and PMNs inner free calcium concentration elevation were inhibited by Kae in a dose-dependent manner. The IC50 of Kae to inhibit platelet adhesion was 65 micromol x L(-1).</p><p><b>CONCLUSION</b>Kae is effective in inhibiting the action of PAF and it is a new PAF receptor antagonist.</p>