title: Decreased calcium content and 45Ca2+ uptake in Down's syndrome blood platelets.
abstract: Total intracellular Ca2+ and 45Ca2+ uptake has been studied in blood platelets from subjects with Down's syndrome and matched controls. In Down's subjects, Ca2+ levels (85.5 +/- 5.9 nmol/10(-9) platelets) were significantly lower than controls, 174 +/- 10.0 nmol/10(-9) (p less than 0.0005). A similar reduction was seen in calcium uptake (Down's platelets, 0.79 +/- 0.06 nmol/10(-9) platelets; controls, 1.17 +/- 0.07 nmol/10(-9) platelets, p less than 0.005). The low levels of intracellular Ca2+ may be related to decreased granular storage of serotonin, and the decreased Ca2+ uptake with impaired transport by intracellular Ca2+-accumulating organelles such as the dense tubular system.
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000378:metabolism*; D002118:Calcium / Q000097:blood*; D002132:Calcium Radioisotopes; D004314:Down Syndrome / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male
chemical_list: D002132:Calcium Radioisotopes; D002118:Calcium