In vitro capacitation and acrosome reaction in sperm of the phyllostomid bat Artibeus jamaicensis

Abstract

Sperm capacitation occurs during the passage of sperm through the female reproductive tract. Once the sperm binds to the pellucid zone, the acrosome reaction to enable penetration of the oocyte is completed. In this study, sperm of Artibeus jamaicensis bat was used to evaluate both capacitation status and the acrosome reaction under in vitro conditions, incubating sperm at 32 and 37°C with and without progesterone. Sperm was incubated at different times to assess sperm cells' functionality in terms of capacitation and acrosome reaction, using the chlortetracycline staining, lectin fluoresceinisocyanate conjugate-Pisum sativum agglutinin (FITC-PSA), and transmission electron microscopy. Sperm cells that presented uniform fluorescence throughout the head and mid-piece were classified as non-capacitated. Subsequently, sperm cells, which were observed with fluorescence only in the anterior portion of the head and mid-piece, were classified as capacitated. Sperm cells with no fluorescence in the head, but fluorescence in the mid-piece, were categorized as sperm cells that have carried out the acrosome reaction. During the acrosome reaction, sperm cells showed changes in their morphology, so it was not possible to distinguish the plasma and acrosomal membranes. Around the entire head, it was not possible to distinguish the fusion points between these membranes that made it possible for the acrosomal reaction to take place and thus to release the enzymes necessary to penetrate the pellucid zone. In conclusion, under appropriate in vitro conditions and by supplementing the culture medium with progesterone, A. jamaicensis bat sperm cells are able to be capacitated in a period from 6 to 8 h and to carry out the acrosome reaction.

Pores Formation in Porcine Sperm Incubated in Streptolysin O and Its Post Thawing Viability after Trehalose Treatment

“…The functional status of spermatozoa was assessed with Chlortetracycline (CTC) (Sigma-Aldrich, St. Louis MO, USA), a fluorescent antibiotic (Álvarez-Guerrero et al, 2016). This assay allows observing changes in the sperm plasma membrane-associated with the capacitation status of the sperm.…”

Caracterización de la capacitación espermática en el murciélago Corynorhinus Mexicanus

“…Por otro lado, Álvarez-Guerrero et al (2016), estudiaron en espermatozoides del murciélago Artibeus jamaicensis de la familia Phyllostomidae, la capacitación y RA en condiciones in vitro a 32 y 37 °C con y sin P4 a diferentes horas (0-8 horas).…”