[Effects of platelet activating factor on release of thromboxane B2 from human granulocytes and platelets].
We investigated the effects of platelet activating factor (PAF) on the release of thromboxane (Tx) B2 from human granulocytes and platelets. Stimulation of human peripheral whole blood cells by PAF (10(-5) M) resulted in the production of TxB2 (p < 0.05). When human granulocyte suspensions (2.0 x 10(6)/ml) were stimulated by calcium ionophore A23187 (10(-5) M), TxB2 levels in the supernatant fluid increased significantly (p < 0.01). However PAF (10(-5) M) did not increase the levels of TxB2 in granulocyte suspensions. In the presence of cytochalasin B (5 micrograms/ml), PAF (10(-8) M, 10(-7) M, 10(-6) M) did not induce any significant release of TxB2 from granulocytes. The levels of TxB2 in human platelet suspensions were significantly increased by PAF (10(-5) M) stimulation (p < 0.05). These results suggest that PAF induces TxB2 release from human platelets, but it may not stimulate the production of TxB2 in human granulocytes.
First Department of Internal Medicine, School of Medicine, Showa University.
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T
Imai
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S
Horikoshi
M
M
Kurokawa
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K
Idaira
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Mita
M
M
Adachi
M
M
Okamoto
D001792:Blood Platelets / Q000378:metabolism*; D002478:Cells, Cultured; D006098:Granulocytes / Q000378:metabolism*; D006801:Humans; D008297:Male; D010972:Platelet Activating Factor / Q000494:pharmacology* / Q000502:physiology; D013929:Thromboxane B2 / Q000378:metabolism*
D010972:Platelet Activating Factor; D013929:Thromboxane B2