Enhancement of Thrombocyte Aggregation and Thromboxane B₂Synthesis by Diethylstilbestrol

Abstract

Effect of diethylstilbestrol administration on thrombocyte aggregation and thromboxane B₂ synthesis was investigated in atherosclerosis-susceptible pigeons. Platelet aggregatory response to arachidonic acid and synthesis of thromboxane B₂ from ¹⁴C-arachidonic acid was enhanced in thrombocytes derived from diethylstilbestrol-treated pigeons. Platelet total phospholipid concentration was increased in pigeons with diethylstilbestrol treatment. Enhanced thromboxane synthesis might be responsible for increased platelet aggregation, which in turn might contribute to the severe atherosclerosis noted following diethylstilbestrol treatment in several avian species.

Effect of Testosterone and Oxandrolone on Thrombocyte Aggregation and Synthesis of Prostaglandins in Thrombocytes and Aorta of Atherosclerosis-susceptible Pigeons*

“…Formation of 6-keto PGFla and PGFza is fairly small in pigeon aorta in accordance with our previous study (Subbiah -1979). The areas corresponding to PGE2, PGF2a thromboxane B2 and 6-keto-PGFia were scraped off into vials and subjected to scintillation counting (Subbiah -1980). Conversion of [ 14Cl-arachidonic acid into various prostaglandins was expressed as dpm product fomed/milligram protein estimated by the procedure of Lowry et al (1951).…”

“…Change in percentage transmission was recorded with a chronolog aggregometer (Havertown, Pa.). For the isolation of thrombocytes (Andreoli -1969;Subbiah et al -1980) to study arachidonic acid metabolism blood was centrifuged at 130 g for 4 min. at 0".…”