Secretion of progesterone in vitro by mature day 8 ovine corpora lutea (CL) of the estrous cycle was increased linearly by ovine LH (1, 10 and 100 ng/ml) or prostaglandin E2 (PGE2) 1, 10 and 100 ng/ml) in a dose dependent manner (P ≤ 0.05). Progesterone secretion in vitro by 88-90 day ovine CL of pregnancy was not affected P ≤ 0.05 by LH (1, 10 and 100 ng/ml) while prostaglandin E1 (PGE1) 1, 10 and 100 ng/ml) increased (P ≤ 0.05) secretion of progesterone in a dose dependent manner and PGE2 (1, 10 and 100 ng/ml) increased (P ≤ 0.05) secretion of progesterone only at the 100 ng/ml dose. Day 8 ovine eL of the estrous cycle did not secrete (P ≤ 0.05) detectable quantities of prostaglandin F2α (PGF2α or prostaglandin E (PGE) while 88-90 day ovine CL of pregnancy secrete PGE (P ≤ 0.05) but not PGF2α (P ≤ 0.05). Regulation of PGE secretion by 88-90 day ovine CL of pregnancy may be via pregnancy specific protein B (PSPB), which increased (P ≤ 0.05) PGE and progesterone but not PGF2α (P ≤ 0.05) secretion. Secretion of progesterone by CL of 88-90 days of pregnancy was not affected by IGF1, IGF2, PAF-16, PAF-18, oxytocin, PGI2, PGD2 or leukotriene C4- (P ≤ 0.05). It is concluded that PGE1 or PGE2 but not LH regulates secretion of progesterone in vitro by 88-90 day ovine CL of pregnancy. In addition, it is concluded that 88-90 day ovine CL of pregnancy secretes it's own luteotropin, which is PGE. Secretion of PGE by ovine CL of pregnancy may be regulated by PSPB.
|Number of pages||17|
|State||Published - May 1997|
Bibliographical noteFunding Information:
This paper is Journal Series No. of the Hawaii Institute of Tropical Agriculture and Human Resources. This research was supported in part by the USDA under CSREES Special Grant No. , to C. Weems managed by the Pacific Basin Advisory Group, USDA Hatch Project (C.W.W.) and Hatch Project (G.R.S.) as Hawaii's and Idaho's contribution to USDA W-112 Regional Research Project. The authors want to thank Dr. L. Levine (Brandeis University) for the antibody to PGF 2 α and Dr. N. Mason, Lily Research Laboratories for the PGE antiserum. The authors want to thank the NIH National Pituitary Hormone Program for purified ovine LH used in these experiments, Mr. Wayne Toma (U.H.) for assistance with statistical analysis and graphics, and Ms. Sharleen Fujimoto (U.H.) for typing the manuscript.
- Corpus luteum
- Luteinizing hormone
ASJC Scopus subject areas