TY - JOUR
T1 - Seasonal changes in luteal progesterone concentration and mRNA expressions of progesterone synthesis-related proteins in the Corpus Luteum of Mares
AU - Kozai, Keisuke
AU - Hojo, Takuo
AU - Takahashi, Masashi
AU - Acosta, Tomas J.
AU - Nambo, Yasuo
AU - Okuda, Kiyoshi
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2012
Y1 - 2012
N2 - Although circulating progesterone (P4) levels tend to change with the season, little is known about the seasonal changes of P4 synthesis-related proteins in the corpus luteum (CL) of mares. To examine these changes, seventy-four ovaries containing a CL were collected from Anglo-Norman mares at a local abattoir in Kumamoto, Japan (~N32°), five times during one year. The stages of the CLs were classified as early, mid and regressed by macroscopic observation of the CL and follicles. The mid CL, which had the highest P4 concentration, was used to evaluate the seasonal changes in P4 synthesis. The luteal P4 concentration and mRNA expression of luteinizing hormone receptor (LHCGR) were lowest during early winter and highest during late winter. The mRNA expressions of steroidogenic acute regulatory protein (StAR), P450 cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase (3β-HSD) were lowest during early winter and increased during late winter. These results suggest that P4 synthesis in the CL is affected by the seasonal changes in the mRNA expressions of P4 synthesis-related proteins in mares.
AB - Although circulating progesterone (P4) levels tend to change with the season, little is known about the seasonal changes of P4 synthesis-related proteins in the corpus luteum (CL) of mares. To examine these changes, seventy-four ovaries containing a CL were collected from Anglo-Norman mares at a local abattoir in Kumamoto, Japan (~N32°), five times during one year. The stages of the CLs were classified as early, mid and regressed by macroscopic observation of the CL and follicles. The mid CL, which had the highest P4 concentration, was used to evaluate the seasonal changes in P4 synthesis. The luteal P4 concentration and mRNA expression of luteinizing hormone receptor (LHCGR) were lowest during early winter and highest during late winter. The mRNA expressions of steroidogenic acute regulatory protein (StAR), P450 cholesterol side-chain cleavage enzyme (P450scc) and 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase (3β-HSD) were lowest during early winter and increased during late winter. These results suggest that P4 synthesis in the CL is affected by the seasonal changes in the mRNA expressions of P4 synthesis-related proteins in mares.
KW - Corpus luteum
KW - Mares
KW - Progesterone
KW - Reproductive seasonality
KW - Steroidogenesis
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U2 - 10.1262/jrd.2012-023
DO - 10.1262/jrd.2012-023
M3 - Article
C2 - 22498814
AN - SCOPUS:84867846615
VL - 58
SP - 393
EP - 397
JO - Journal of Reproduction and Development
JF - Journal of Reproduction and Development
SN - 0916-8818
IS - 4
ER -