Serotonin uptake at 22 degrees C of stored platelets.
In order to ascertain the possibility that platelet serotonin uptake may occur during storage of platelet concentrates (PC) at 22 degrees C with agitation, the high-performance liquid chromatographic procedure was applied to determine serotonin uptake by platelets. Studies at 22 degrees C showed that platelets stored for 4 days exhibited a significant serotonin uptake with a Vmax value of 2.4 X 10(-19) mole/platelet/min and a Km value of 0.62 X 10(-6) M. Incubation of PC with 5 X 10(-6) M serotonin for 1 day at 22 degrees C increased their serotonin contents from 2.2 to 4.2 X 10(-7) mole/10(11) platelets. Thrombin stimulation caused about 80% release of intracellular serotonin from fresh as well as stored platelets, which contained standard serotonin in the same amount as the original amount. These results suggest that a significant serotonin uptake of platelets might occur during in vitro storage at 22 degrees C and stored platelets have retained abilities to sequester extracellular serotonin into dense granules.
D001792:Blood Platelets / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D012701:Serotonin / Q000097:blood*; D013696:Temperature; D013917:Thrombin / Q000494:pharmacology
D012701:Serotonin; D013917:Thrombin