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The effects of basal LH inhibition with Cetrorelix on cumulus cell gene expression during the luteal phase under ovarian coasting stimulation in cattle.

ABSTRACT: impact of suppressing LH using the GnRH antagonist Cetrorelix during an ovarian coasting stimulation protocol on the transcriptome of bovine cumulus cells (CC). Oocytes were collected twice from six dairy cows. For the first collection, the cows received FSH twice daily for three days, followed by FSH withdrawal for 68 hours as control protocol. For the second collection, the same stimulation protocol was used, but the cows also received, starting on day 2 of FSH stimulation, a GnRH antagonist once a day until recovery of the cumulus-oocyte complexes (COC). Half of the COC were subjected to in vitro maturation, fertilization and culture to assess blastocyst rates. The other half of the CC underwent microarray analysis (n=3 cows, 2 treatments, 6 oocyte collections) and qRT-PCR (n=6 cows: 3 microarray cows + 3 other cows, 2 treatments, 12 oocyte collections). The differential expression of specific genes was confirmed by RT-qPCR: ATP6AP2, SC4MOL, OSTC and PTGDS. The global transcriptomic analysis of cumulus cells demonstrated that the inhibition of LH secretion may decrease survival, and growth of the follicle. Moreover, the results suggested that LH may be important to cumulus for the maintenance of cellular mechanisms such as global RNA expression, protein and nucleic acid metabolism and energy production. These results support the hypothesis that LH support is important during the final part of follicle maturation through its influence on the cumulus cells.

ORGANISM(S): Bos taurus

PROVIDER: GSE121783 | GEO | 2018/10/26

REPOSITORIES: GEO

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The effects of basal LH inhibition with Cetrorelix on cumulus cell gene expression during the luteal phase under ovarian coasting stimulation in cattle.

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