RAO, V.H(MAJOR)SIVA KUMAR, A.V.NVEERABRAHMAIAH, KPRABHAVATHI, T2018-11-302018-11-302015-11http://krishikosh.egranth.ac.in/handle/1/5810084873THESESABSTRACT : The present study was conducted to know the influence of Leptin on the expression of p53 and BAK (apoptotic) genes in the sheep preantral follicles (PFs’) cultured in vitro. Ovaries of sheep were collected from the local slaughter house. Intact PFs’ (250-400μm) were isolated and placed individually in 20μl droplets of standard medium (TCM 199 B + 2 μg/ml FSH, 0.1μg/ml T4 + 10 ng/ml IGF-I + 1 mIU/ml of GH) supplemented with Leptin (10ng/ml) for 2, 4 or 6 days. Quantitative expression of Test genes (p53 and BAK) and Reference genes (18s RNA, RPLPO, HPRT1) were studied in the cumulus cells and oocytes isolated at different developmental stages (preantral, early antral, antral and large antral follicles) of the in vivo and in vitro grown follicles. The entire experiment was repeated twice. Duplicate samples of cDNA from each replicate of the experiment were subjected to relative-RT-qPCR. The pattern of expression of p53 gene in the cumulus cells from ovarian follicles grown in vivo and cultured in Leptin was similar from preantral to large antral follicle stage. In the oocytes, however, such similarity was restricted up to the antral follicle stage only. It is concluded that Leptin in culture medium mimiced the pattern of p53 expression in in vitro as in in vivo to some extent. The BAK gene expression was undetected in the cumulus cells and oocytes isolated from all the stages of both in vivo and in vitro developed ovarian follicles. Accordingly it is concluded that (i) Leptin has no influence on the expression of BAK gene in cultured ovarian follicles in sheep (ii) BAK may not be an important regulator of apoptosis in ovarian follicles and (iii) p53 plays a relatively more significant role than BAK in the regulation of apoptosis in ovarian follicles.ennullThesis