title: Sex-related differences in platelet morphology in whole blood (WB) and platelet-rich plasma (PRP).
abstract: The proportion of smooth, disc-shaped platelets (D) in freshly drawn, glutaraldehyde fixed whole blood (WB) and citrated platelet-rich plasma prepared at 37 degrees C is compared for male (N = 55) and female (N = 31) donors. Female donors have significantly more %D than male donors and the variability in %D measured on repeated occasions over a period of 3-69 months is less for female donors. WB and PRP gave similar results. The sex-related differences in %D were not related to hematocrit or to concomitant use of oral contraceptives. There were no significant sex-related differences in platelet mean volume or in platelet plasma membrane surface area as determined by the osmotic spherocyte method. However, the volume of D is smaller for male donors. It is concluded that the sex-related differences in platelet morphology do not represent intrinsic differences in platelet size or measurable total plasma membrane but represent a selective shape change activation of the larger D in the circulation of male donors. The significance of these observations for the sex-related differences in risk of cardiovascular disease and efficacy of anti-thrombotic therapy awaits appropriate prospective epidemiological studies.
mesh_terms: D000293:Adolescent; D000328:Adult; D001792:Blood Platelets / Q000166:cytology* / Q000187:drug effects; D003276:Contraceptives, Oral / Q000009:adverse effects; D005260:Female; D006400:Hematocrit; D006801:Humans; D008297:Male; D012737:Sex Factors
chemical_list: D003276:Contraceptives, Oral