Objective: To determine the presence of the platelet-activating factor (PAF) receptor on human spermatozoa.
Design: Prospective analysis.
Setting: University-based reproductive biology laboratory.
Patient(s): Spermatozoa obtained from men undergoing routine semen analysis.
Intervention(s): Spermatozoa (n = 10) were exposed to PAF, sheep anti-PAF antibody, and fluorescein isothiocyanate-conjugated rabbit antisheep antibody, and then evaluated by fluorescent microscopy.
Main outcome measure(s): Assessment of fluorescent intensity at four locations on the spermatozoa (tail, midpiece, proximal head, and acrosome region).
Result(s): Immunofluorescence demonstrated the presence of the PAF receptor on human spermatozoa. The PAF receptor was most prevalent at two sites on the spermatozoa: the midpiece and the proximal head.
Conclusion(s): The PAF receptor is present on human spermatozoa. Platelet-activating factor may affect the motility of spermatozoa through a receptor-mediated mechanism at the midpiece and/or proximal head.