Total content of prostaglandin F2 alpha in the endometrium and myometrium from various sections of the porcine uterine horn during the estrous cycle.

The purpose of this study was to determine effects of various stages of the estrous cycle on the content and concentration of PGF2 alpha in endometrium and myometrium in different segment of the uterine horn and whether different methods of expressing PGF2 alpha data would affect interpretation of results. Total content of PGF2 alpha in the endometrium and myometrium of the entire uterine horn, and PGF2 alpha concentrations in five sections of uterine horn each of equal length (1 to 5 beginning from the ovarian end) were measured in gilts during three different phases of the estrous cycle: the early luteal phase (Days 3 to 6 of the estrous cycle), mid-luteal phase (Days 9 to 12), and during luteolysis (Days 15 to 18). The total content of PGF2 alpha in the early and mid-luteal phases was similar (P > or = 0.05) in both the endometrium and myometrium. During luteolysis the content of PGF2 alpha in the endometrium and myometrium increased 7-fold and 4-fold, respectively, when compared to the early luteal phase. The distribution of PGF2 alpha was similar throughout the length of the uterine horn and this did not change during the phases of the cycle studied. The PGF2 alpha concentrations during different phases of the estrous cycle differed with methods of expressing the data i.e. ng g-1 tissue, ng mg-1 DNA, ng mg-1 protein, but the relative differences were not appreciably altered.