[Study of the induction of thrombocyte adhesiveness in the presence of heparin]

An investigation of the thrombocytes adhesion after Hellem (1960) showed that "in vitro" tests norepinephrine, epinephrine, histamine, serotonin and adenosine-diphosphate, when used in doses of 100-25,0 gamma/ml, were capable of raising the thrombocytes adhesion, while heparin administered in doses of 0.5-0.05 U/ml depressed and in a dose of 0.025 U/ml mildly activated this capacity of the thrombocytes. In the presence of heparin the ability of biogenic amines to induce the adhesion of thrombocytes decreased. Between concentration of the agents and the adhesive index of thrombocytes there exists a two-way logarithmic relationship. Intravenous administration of serotonin in a dose of 5 mg/kg and of epinephrine in an amount of 0.05 mg/kg to rabbits increased the adhesivity of thrombocytes, whereas intravenous introduction of 100 un/kg of heparin tended to greatly reduce it. On introduction of serotonin and epinephrine to rabbits against the background of heparin their ability to activate the thrombocytes adhesion diminished quite significantly. The logarithm of time lapsed from the instance of the heparin administration is linearly dependent on the logarithms of values characterizing the adhesivity of thrombocytes. Intravenous administration of norepinephrine and histamine in a dose of 0.5 mg/kg did not cause any changes in the adhesive properties of thrombocytes.