FURTHER STUDIES ON THE INFLUENCE OF HISTAMINE ON PLATELET ACTIVITY, WITH ESPECIAL REFERENCE TO ITS ACTION ON THE BLOOD OF THE HEMOPHILIAC PATIENT

[摘要] Clinically and experimentally intravenous and subcutaneous injections of histamine increase directly the qualitative disintegrative ability of the blood platelets. It has no effect on the total platelet count (quantitative action) until shocklike levels are obtained. It then causes a decrease in the number of the circulating platelets in the blood.This qualitative action may be in part due to an antagonistic action between heparin and histamine. Heparin in high concentrations does not inhibit completely the increased tendency toward in vitro agglutination of the platelets exposed in vivo to histamine.In 22 hemophiliac boys, intravenous and subcutaneous injections of histamine decreased the coagulation time of the blood by increasing the platelet disintegration in 19 patients. It was a complete failure in three of the boys. The action of the histamine is not permanent, and tends to become less efficient as more injections are given. However, it is sufficient to cause a cessation of bleeding and to decrease the coagulation time of the blood to its normal value for that person in the majority of instances.

[学科分类] 儿科学