Biology of Reproduction, Vol 27, 431-439, Copyright © 1982 by Society for the Study of Reproduction

ARTICLES

Metabolism of arachidonic acid in vitro by bovine blastocysts and endometrium

GS Lewis, WW Thatcher, FW Bazer and JS Curl

Metabolism of arachidonic acid and prostaglandin F2 alpha by bovine blastocysts and endometrial slices recovered on Days 16 and 19 postmating was studied in vitro. In Experiment 1, arachidonic acid (10 microCi tritiated and 200 micrograms radioinert) was added to blastocysts and endometrial slices prior to incubation for 24 h. [3H]arachidonic acid ([3H]AA) and metabolites in extracts of culture medium and tissue homogenates were separated on columns of Sephadex LH- 20. Elution profiles of [3H]AA and metabolites in extracts of culture medium revealed that 13, 14-dihydro-15-keto-PGF2 alpha (PGFM), Pge2, PGF2 alpha, and at least four unidentified compounds were produced by Day 16 and Day 19 blastocysts. Endometrial slices from both days of pregnancy produced 3H-prostaglandins. Experiment 2 was conducted to quantify PGE2, PGF2 alpha and PGFM in aliquots of culture medium from Day 16 and Day 19 blastocyst and endometrial incubates. These tissues were incubated with 200 micrograms of radioinert arachidonic acid. Day 16 blastocysts produced less (microgram/blastocyst; P less than 0.01) of each prostaglandin than Day 19 blastocysts (PGE2, 0.7 +/- 0.4 vs. 4.2 +/- 1.0; PGF2 alpha, 2.1 +/- 0.7 vs. 22.8 +/- 4.1; PGFM, 0.03 +/- 0.01 vs. 0.5 +/- 0.2). Endometrial slices produced PGE2, PGF2 alpha and PGFM, but quantities were not affected by day postmating or uterine horncorpus luteum relationships. The third experiment was conducted to determine directly if Day 19 blastocysts and endometrial slices metabolized [3H]PGF2 alpha to [3H]PGFM. Blastocysts and endometrial slices produced [3H]PGFM. Endometrial slices metabolized 34.3 +/- 1.5% of the [3H]PGF2 alpha to [3H]PGFM, while blastocysts metabolized 7.5 +/- 1.6% of the [3H]PGF2 alpha to [3H]PGFM. Results of this study indicate that bovine blastocysts and endometrial slices can metabolize [3H]AA in vitro. It is postulated that prostaglandins of blastocyst and endometrial orgin have a role in maintenance of early pregnancy in cattle.

This article has been cited by other articles:

				A. Waclawik and A. J Ziecik Differential expression of prostaglandin (PG) synthesis enzymes in conceptus during peri-implantation period and endometrial expression of carbonyl reductase/PG 9-ketoreductase in the pig J. Endocrinol., September 1, 2007; 194(3): 499 - 510. [Abstract] [Full Text] [PDF]

				T. R. Bilby, A. Guzeloglu, L. A. MacLaren, C. R. Staples, and W. W. Thatcher Pregnancy, Bovine Somatotropin, and Dietary n-3 Fatty Acids in Lactating Dairy Cows: II. Endometrial Gene Expression Related to Maintenance of Pregnancy. J Dairy Sci, September 1, 2006; 89(9): 3375 - 3385. [Abstract] [Full Text] [PDF]

				A. Guzeloglu, T. R. Bilby, A. Meikle, S. Kamimura, A. Kowalski, F. Michel, L. A. MacLaren, and W. W. Thatcher Pregnancy and Bovine Somatotropin in Nonlactating Dairy Cows: II. Endometrial Gene Expression Related to Maintenance of Pregnancy J Dairy Sci, October 1, 2004; 87(10): 3268 - 3279. [Abstract] [Full Text] [PDF]

				V. Emond, L. A. MacLaren, S. Kimmins, J. A. Arosh, M. A. Fortier, and R. D. Lambert Expression of Cyclooxygenase-2 and Granulocyte-Macrophage Colony-Stimulating Factor in the Endometrial Epithelium of the Cow Is Up-Regulated During Early Pregnancy and in Response to Intrauterine Infusions of Interferon-{tau} Biol Reprod, January 1, 2004; 70(1): 54 - 64. [Abstract] [Full Text] [PDF]

				H. Ni, T. Sun, N.-Z. Ding, X.-H. Ma, and Z.-M. Yang Differential Expression of Microsomal Prostaglandin E Synthase at Implantation Sites and in Decidual Cells of Mouse Uterus Biol Reprod, July 1, 2002; 67(1): 351 - 358. [Abstract] [Full Text] [PDF]