FIBRONECTIN MODULATES ENDOCANNABINOID SYSTEM IN BOVINE SPERM CAPACITATION

OSYCKA SALUT C; CASTELLANO L; ALONSO CAI; DIAZ ES; PEREZ MARTINEZ S

Chascomus, Buenos Aires

Jornada; XVI ANNUAL MEETING OF THE ARGENTINE BIOLOGY SOCIETY; 2014

Sociedad Argentina de Biología

Anandamide (AEA), a major endocannabinoid, binds to cannabinoid and vanilloid receptors (CB1, CB2 and TRPV1). In addition, Fibronectin (Fn) is a glycoprotein from extracellular matrix. Both molecules affect many reproductive functions. Previously we found that AEA and Fn regulate bovine sperm capacitation through CB1 and TRPV1. Here we investigated the regulation of the endocannabinoid system during capacitation by Fn in bovine spermatozoa (SPZ). To perform sperm capacitation, SPZ were incubated in spTALP and Fn during 45 min. Sperm capacitation was evaluated by CTC and LPC-induced acrosome reaction. Fn induced changes in the location of sperm TRPV1. Also, FAAH (enzyme that hydrolyses AEA) activity was measured by radioimmunoassay. FAAH activity was modulated in SPZ incubated with Fn. To investigate nitric oxide (NO) production, SPZ were incubated with Fn and capsazepin (a TRPV1 antagonist) and DAF-FM probe (fluoresce in presence of NO). The fluorescent complex was measured by flow cytometry. Fn increased sperm NO levels and the preincubation with capsazepin reversed Fn induction. Finally, Fn up-regulated PKA substrates phosphorylation such as AEA. The results suggest that Fn, through endocannabinoid system activation, induces events associated to sperm capacitation in bovines.