Only a subpopulation of mouse sperm displays a rapid increase in intracellular calcium during capacitation.

BUFFONE MG; GILIO N; PUGA MOLINA LC; DALOTTO-MORENO T; KRAPF D; ROMAROWSKI A; MARTÍN-HIDALGO D; VISCONTI PE; BALESTRINI PA; RITAGLIATI C; LUQUE GM

Ciudad Autonoma de Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias.; 2017

Freshly ejaculated mammalian sperm do not have the ability to fertilize oocytes. They must undergo a functionally defined process called capacitation. Sperm become capacitated in vivo by interacting with the female reproductive tract or in vitro in a defined capacitation media that contains bovine serum albumin (BSA), calcium (Ca2+) and bicarbonate (HCO3-). In this work, we used flow cytometry to qualitatively analyze changes in intracellular Ca2+ concentration ([Ca2+]i). For this purpose, sperm were double stained with Propidium iodide and the Ca2+ dye Fluo-4 AM to analyze these changes in individual live sperm. An increase in [Ca2+]i was observed in capacitated live sperm when compared with non-capacitated ones, being able to distinguished one subpopulation of sperm more responsive than the other. These rise in [Ca2+]i after 90 min of incubation in capacitated media was evidenced by an increase in the normalized median fluorescence (p