Thrombin and lonophore A23187-Induced Dense Granule Secretion in Storage Pool Deficient Platelets: Evidence for Impaired Nucleotide Storage as the Primary Dense Granule Defect
نویسندگان
چکیده
The secretion of the dense granule constituents ATP. ADP, calcium. pyrophosphate (PP,). and orthophosphate (PJ. and the release of magnesium induced by thrombin and the divalent cation ionophore A231 87 have been quantitated directly in gel-filtered platelets from patients with storage pool deficiency (SPD). Both the contents and the maximal amounts of the dense granule constituents secretable by thrombin were decreased in all the patients studied, while the nonsecretable. retained amounts of these substances were identical in SPD and normal platelets. In response to both thrombin and A231 87, the amounts of secretable ATP and ADP were strongly correlated in the platelets of individual patients; in contrast, secretable calcium showed no correlation with the nucleotides. and significant amounts of calcium were secreted in the total absence of nucleotide secretion in the platelets of several patients.
منابع مشابه
Thrombin and ionophore A23187-induced dense granule secretion in storage pool deficient platelets: evidence for impaired nucleotide storage as the primary dense granule defect.
The secretion of the dense granule constituents ATP, ADP, calcium, pyrophosphate (PPi), and orthophosphate (Pi), and the release of magnesium induced by thrombin and the divalent cation ionophore A23187 have been quantitated directly in gel-filtered platelets from patients with storage pool deficiency (SPD). Both the contents and the maximal amounts of the dense granule constituents secretable ...
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