Prostaglandin F2α upregulates Slit/Robo expression in mouse corpus luteumduring luteolysis.

Prostaglandin F2α (PGF2α) is a key factor in the triggering of the regression of the corpus luteum (CL). Furthermore, it has been reported that Slit/Robo signaling is involved in the regulation of luteolysis. However, the interactions between PGF2α and Slit/Robo in the progression of luteolysis remain to be established. This study was designed to determine whether luteolysis is regulated by the interactions of PGF2α and Slit/Robo in the mouse CL. Real-time PCR and immunohistochemistry results showed that Slit2 and its receptor Robo1 are highly and specifically co-expressed in themouse CL. Functional studies showed that Slit/Robo participates in mouse luteolysis by enhancing cell apoptosis and upregulating caspase3 expression. Both in vitro and in vivo studies showed that PGF2α significantly increases the expression of Slit2 and Robo1 during luteolysis through protein kinase C-dependent ERK1/2 and P38 MAPK signaling pathways, whereas an inhibitor of Slit/Robo signaling significantly decreases the stimulating effect of PGF2α on luteolysis. These findings indicate that Slit/Robo signaling plays important roles in PGF2α-induced luteolysis by mediating the PGF2α signaling pathway in the CL. [ABSTRACT FROM AUTHOR]