Increased number and clumping of thrombocytes (platelets) in pigeons produced by agents causing anaphylactoid reactions

A variety of agents, previously reported by Hanzlik and Karsner cause anaphylactoid reactions when injected intravenously. With many of these emboli and thrombi composed of red blood corpuscles, fibrin and platelets are demonstrable in the lungs, and hemagglutination occurs in vitro. These changes together with the alterations in chemical composition of the blood recently demonstrated in this laboratory, are regarded as objective evidences of disturbances in important physical and chemical equilibria in the fluids and tissues of the organism, and as being of fundamental importance in the explanation of reactions from a variety of agents. The present report is a summary of the effects of different agents upon the thrombocytes (platelets) in pigeons.

For differentiation, the modified Nocht stain described by Hastings 1 was used and for counting, a modification of the cresyl violet stain of Buckman and Hallisey. 2 All agents were injected intravenously at body temperature into the wing veins and blood was obtained from superficial veins of the legs.

The following agents, which cause anaphylactoid symptoms in guinea pigs, pulmonary emboli and thrombi, and hemagglutination in vitro, produced increases in number and clumping of thrombocytes in pigeons; peptone, agar-sol gel, toxified agar, Congo red, collargol, charcoal, kaolin, colloidal iron, colloidal arsenic, 50 per. cent. acetic acid and 6 per cent. acacia. Histamin, tannin and arsphenamin (in small dosage) produced doubtful or no changes in the thrombocytes, but sections of lungs and livers showed marked clumping of erythrocytes from these agents.

Histological examinations of the lungs, liver, spleen and kidneys of all animals showed congestion and thrombosis after the majority of the agents that were injected. In a few cases marked hemorrhages were found. The majority of these agents caused definite symptoms, ranging from shivering, crouching, and increase in respiration to death.