Storage Pool Disease: Comparative Fluorescence Microscopical, Cytochemical and Biochemical Studies on Amine‐Storing Organelles of Human Blood Platelets

Abstract

S ummary . The platelet content of ATP, ADP, serotonin (5‐HT), dopamine, noradrenaline and adrenaline as well as the net uptake of radiolabelled 5‐HT and mepacrine were subnormal in six patients with Storage Pool Disease (SPD). Fewer amine‐storing organelles were found by fluorescence microscopy with the fluorescent probe mepacrine and by electron microscopy with a cytochemical (uranaffin) reaction specific for 5′‐phosphonucleotides. Both methods showed that SPD platelets have atypical organelles with a reduced capacity to store amines, 5′‐phosphonucleotides and mepacrine. The changes were most marked in platelets of the two patients who also had oculocutaneous albinism.