Abnormal platelet function in Chediak-Higashi syndrome.
Platelets in an infant with Chediak-Higashi (C-H) syndrome without bleeding manifestations and not in the accelerated phase showed abnormal function consistent with storage pool disorder as shown by abnormal aggregation, decreased storage capacity and release of [14C]5-HT, low endogenous 5-HT, reduced ATP and ADP with an increased ATP/ADP ratio, increased specific radioactivity of ADP after [14C]adenine labelling, decreased release of adenine nucleotides after stimulation, impaired secretion of acid hydrolases despite normal stores, and decreased calcium content. Incorporation of [14C]adenine into metabolic pool adenine nucleotides was normal. Nucleotide conversion to hypoxanthine in stimulated platelets was mildly impaired. Platelet cyclic-AMP (c-AMP) was initially elevated, but even when c-AMP returned to normal levels after ascorbate treatment, platelet function was not improved. Elevated intracellular c-AMP was not solely responsible for the abnormal platelet function.
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D002609:Chediak-Higashi Syndrome / Q000503:physiopathology*; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D006801:Humans; D006867:Hydrolases / Q000378:metabolism; D007223:Infant; D010974:Platelet Aggregation; D012701:Serotonin / Q000378:metabolism; D013917:Thrombin / Q000494:pharmacology
D012701:Serotonin; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D006867:Hydrolases; D013917:Thrombin