title: Imparied platelet--dense granule release in neonates.
abstract: OBJECTIVE
  The aim of this study is to examine differences in platelet dense granule (PDG) uptake and release between preterm infants, term infants, and adults.
  
  
  METHODS
  PDG uptake and release was examined by flow cytometry using mepacrine fluorescent staining in phycoerythrin-anti-GPIIb/IIIa bound platelets taken from cord blood of eight term infants and seven preterm infants and venous blood from eight adults.
  
  
  RESULTS
  Analysis of the baseline fluorescence in the untreated versus thrombin-treated samples revealed significant differences in the way infant PDGs responded to thrombin stimulation when compared with adults. Initial uptake of mepacrine in both term and preterm platelets was similar to that in adult platelets. Statistically significant differences between adults and both term and preterm infants, at two concentrations of mepacrine, were observed after stimulation with thrombin.
  
  
  CONCLUSIONS
  Persistent mepacrine staining of infant PDGs, when compared with those of adults, after thrombin stimulation implies defective infant PDG release. This may partially explain why infants have impaired response to agonists requiring ATP release from PDGs.
authors.affiliation: Pediatrics Department, University of Illinois College of Medicine at Peoria, USA.
authors.forename: P
authors.initials: P
authors.lastname: Mankin
authors.forename: J
authors.initials: J
authors.lastname: Maragos
authors.forename: M
authors.initials: M
authors.lastname: Akhand
authors.forename: K L
authors.initials: KL
authors.lastname: Saving
mesh_terms: D000328:Adult; D001792:Blood Platelets / Q000502:physiology*; D015550:Cell Degranulation; D003594:Cytoplasmic Granules; D005312:Fetal Blood; D005434:Flow Cytometry; D006801:Humans; D007231:Infant, Newborn