Vascular thromboxane formation in hemostasis mechanism: correlation between bleeding time and vascular TXB2 in a patient with congenital platelet cyclo-oxygenase deficiency.
We encountered a patient with congenital platelet cyclo-oxygenase deficiency with normal ability to synthesize vascular prostaglandin I2 (PGI2) and thromboxane A2 (TXA2). The patient's peripheral blood monocytes did not show cyclo-oxygenase (COX) activity, but cultured bone marrow fibroblasts showed COX activity. To determine the mechanism of primary hemostasis in this patient, we examined the effect of oral administration of aspirin (1 g) on bleeding time and thromboxane B2 (TXB2), 6-keto prostaglandin F1 alpha (6-keto-PGF1 alpha) production in the blood emerging from the incision in this patient. The bleeding time was markedly prolonged by the administration of aspirin, and this prolongation was associated with the inhibition of TXB2 in the effluent blood, which seemed to be derived from the vessel wall. These findings suggest that vascular TXA2 production plays an important role in the maintenance of hemostasis.
Fuse
I
I
First Department of Internal Medicine, Niigata University School of Medicine, Japan.
Ootsuka
T
T
Hattori
A
A
Mito
M
M
Shibata
A
A
D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood; D000284:Administration, Oral; D000328:Adult; D001158:Arteries / Q000187:drug effects / Q000378:metabolism; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001760:Bleeding Time; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology*; D001853:Bone Marrow / Q000473:pathology; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000201:enzymology*; D011464:Epoprostenol / Q000096:biosynthesis; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D006474:Hemorrhagic Disorders / Q000201:enzymology / Q000235:genetics; D006801:Humans; D007527:Isoenzymes / Q000235:genetics; D009000:Monocytes / Q000187:drug effects / Q000201:enzymology; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000172:deficiency* / Q000235:genetics; D013929:Thromboxane B2 / Q000097:blood*; D014599:Uterus / Q000098:blood supply
D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D010975:Platelet Aggregation Inhibitors; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D011451:Prostaglandin-Endoperoxide Synthases; D001241:Aspirin