The exchangeable splenic platelet pool in response to intravenous infusion of isoprenaline.
8 healthy volunteers and 4 asplenic subjects, in whom autologous platelets had been labelled with radioactive sodium chromate, received i.v. infusions of isoprenaline in a dose of 0.03 microgram x kg-1 x min-1 over a period of 6 min. In the former group these infusions caused a significant decrease in the concentration of labelled as well as unlabelled platelets in the peripheral blood. Body surface countings showed that a significant increase in the count rate over the spleen occurred concomitantly with the decrease in the circulating platelet-bound radioactivity (PBR). In the group of asplenic subjects no change in PBR occurred. It is concluded that adrenergic beta-receptor stimulation causes a transitory trapping of platelets in the exchangeable splenic platelet pool.
D000328:Adult; D000368:Aged; D001772:Blood Cell Count; D001792:Blood Platelets / Q000187:drug effects*; D002860:Chromium Radioisotopes; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D007545:Isoproterenol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D013154:Spleen / Q000502:physiology*; D013156:Splenectomy
D002860:Chromium Radioisotopes; D007545:Isoproterenol