OOCYTE RETENTION IN ACCESSORY CORPORA LUTEA AND ANOVULATION IN THE SOUTH AMERICAN PLAINS VIZCACHA (Lagostomus maximus).

CAPRINO MERCADO R1,3,DUCHOVNY F1,3, VAVRA MS1,3, , CORTASA S1,2, PROIETTO S1,2, CORSO MC1,2, VITULLO AD; HALPERIN J; DORFMAN BERTA VERONICA

Mar del Plata

Congreso; LXIV Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica.; 2019

Sociedad Argentina de Investigación Clínica

The plain vizcachashows unusual reproductive characteristicslikeinhibition of follicular atresia, natural massive poliovulation and reactivation of reproductive axis during pregnancy with follicular recruitmentand formation of accessory corporalutea with oocyte retention at mid-gestation. Oocyte retention is also observed in human pathologies as polycystic ovary syndrome (POS) where follicular cystic formation with oocyte retention results in anovulation. In addition, POS is characterized by alteration in the hormonal environment with androgenic increments. Here we evaluated the oocyte retention and the role of accessory corporaluteain the vizcacha during gestation.Comparison with follicular cysts in POS was analyzed. Non-pregnant non-ovulating (NPNO), non-pregnant ovulating (NPO) and mid-pregnant (MP, 77-95 days of pregnancy) vizcachas were used (n=5 per group). Levels of serum progesterone (P4), estradiol (E2), estrone (E1), androstenedione (A4), and testosterone (TT) were studied by ELISA, and serum luteinizing hormone (LH) by RIA. Ovarydynamic was evaluated by H&E staining, and expression of aromatase (ARO) and 17-HSD enzymes, and LH receptor (LHR) and FSH receptor (FSHR) was determined by immunohistochemistry (IHQ). NPO showed significant increment of P4 related to NPNO whereas, MP showed the highest values (P