Changes on corpus luteum structure and progesterone synthesis pathway after hCG or GnRH treatment during the early luteal phase in sheep

FERNÁNDEZ, JIMENA; BRUNO-GALARRAGA, MARÍA MACARENA; CUETO, MARCELA ISABEL; BONADEO, NADIA; NOTARO, ULISES; SOTO, ANDRÉS TELÉSFORO; DE LA SOTA, RODOLFO LUZBEL; SALVETTI, NATALIA RAQUEL; BIANCHI, CAROLINA PAULA; CRISTINA, CAROLINA; ORTEGA, HUGO HÉCTOR; GIBBONS, ALEJANDRO EDUARDO; LACAU-MENGIDO, ISABEL MARÍA

ANIMAL REPRODUCTION SCIENCE

ELSEVIER SCIENCE BV

Año: 2024 vol. 265

0378-4320

This study investigated the effect of hCG or GnRH on structural changes of the corpora lutea (CL)and the regulation of the expression of steroidogenic enzymes involved in P4 secretion in postovulatory(po-CL) and accessory CL (acc-CL). Sixty-four ewes were assigned to three groupsreceiving: 300 IU of hCG (hCG) or 4 μg Buserelin (GnRH) or 1 mL of saline solution (Control) onDay (d) 4 post artificial insemination (FTAI). Laparoscopic ovarian were performed on d 4, 14and, 21 post-FTAI to determine the numbers of CL. Blood samples were collected for serum LHand P4 analysis. On d 14 post-FTAI, both CL were removed from the ovary to determine largeluteal cell (LLC) number and to evaluate the expression of steroidogenic enzymes (HSD3B1,STAR, CYP11A1). Only hCG and GnRH treated ewes generated acc-CL. The LLC in both po- andacc-CL were significantly greater in the hCG group compared