Involvement of protein cAMP-dependent kinase, phospholipase A2 and phospholipase C in sperm acrosome reaction of Chinchilla lanigera.

GRAMAJO BÜHLER MC; L. ZELARAYÁN; G.SÁNCHEZ TORANZO

REPRODUCTION IN DOMESTIC ANIMALS (1990)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016 vol. 51 p. 150 - 157

0936-6768

The mechanisms involved in fertilization are the center of attention in order to determine the conditions required to reproduce in vitro the events that take place in vivo, with special interest in endangered species. Previous data from mouse sperm, where acrosome reaction (AR) occurs more often in the interstitium of the cumulus oophorus, contribute to strengthen the use of progesterone as a physiological inducer of this process. We studied the participation of protein kinase A (PKA), phospholipases A2 and C (PLA2, PLC) in the AR induced by progesterone from Chinchilla epididymal spermatozoa. The addition of dbcAMP to the incubation medium caused an increase of 58% in the AR, while the use of H89 (30µM), a PKA inhibitor, reflected a decrease of 40% in the percentage of reacted gametes. The assays conducted with arachidonic acid showed a maximum increase of 23% in the AR. When gametes were preincubated with PLA2 inhibitors, a dose dependent inhibitory effect was observed. The addition of phorbol12-myristate13-acetate (10µM), revealed higher percentages of AR induction (60%).When PLC was inhibited with neomycin and U73122, a dose-dependent decrease in AR percentages was observed. Combined inhibition of PKA, PLA2 and PLC, AR values similar to control were obtained. This work shows evidence, for the first time in Chinchilla, that progesterone activates the AC/cAMP/PKA system as well as sperm phospholipases, and that these signaling pathways participate jointly and cooperatively in AR. These results contribute to the understanding of the complex regulation that is triggered in sperm after the effect of progesterone.