Quantitation of intraplatelet Ca++ deposits as a potential marker of senility

Carlo Bertoni-Freddari, LuciaNno Galeazzi, Tiziana Casoli, Patrizia Fattoretti, Ugo Caselli, Roberta Paoloni

Research output: Contribution to journalArticlepeer-review


OBJECTIVE: To perform a morphometric evaluation of calcium deposits in human platelets as a quantitative procedure to seek a potential marker of senility in a peripheral cellular model. STUDY DESIGN: In human blood samples from middle-aged, healthy volunteers, the intraplatelet calcium content was cytochemically evidenced by the oxalate-pyroantimonate (OPA) reaction. The number and area of OPA aggregates per square micrometer of total sampled area, the area of the deposits per square micrometer of platelet surface and the percentage of positive platelets were the ultrastructural features calculated by computer-assisted image analysis. RESULTS: OPA precipitates were easily identified in all the samples evaluated. The area of OPA deposits per square micrometer of platelet surface was rather constant not only among the measurements performed on the same sample but also comparing the different subjects analyzed. Other OPA deposit features showed higher variabilities; thus, to obtain a representative sample from each patient, several measurements had to be carried out. CONCLUSION: Quantitation of calcium deposits may be of help in evidencing increased Ca++ sequestering activity by platelets, supposedly due to altered calcium homeostasis. The OPA cytochemical procedure visualizes millimolar quantities of Ca++ ions; thus, only high calcium concentration sites (granules) can be detected by morphometric methods.

Original languageEnglish
Pages (from-to)517-520
Number of pages4
JournalAnalytical and Quantitative Cytology and Histology
Issue number6
Publication statusPublished - Dec 1999


  • Alzheimer disease
  • Calcium
  • Platelets

ASJC Scopus subject areas

  • Anatomy
  • Histology
  • Cell Biology


Dive into the research topics of 'Quantitation of intraplatelet Ca++ deposits as a potential marker of senility'. Together they form a unique fingerprint.

Cite this