Contractile effect of PGF2α and PGE2 on isolated branches of uterine and ovarian artery in different days of estrous cycle and early pregnancy in pigs

Abstract

The contractile effects of PGF 2 α (3 × 10 -6 to 10 -4 M) and PGE 2 (10 -7 to 10 -5 M) were examined on isolated branches of ovarian artery (OA) and extramyometrial branches of uterine artery (UA) collected from pigs in the luteal (day 10-12) and follicular phase (day 17-20) of the estrous cycle, and during early pregnancy (day 10-12). Strong contraction was demonstrated in both arteries during all investigated periods in response to PGF 2 α, which was significantly higher (P < 0.01) than to PGE 2 , being negligible in the follicular phase. In UA, the effective dose of PGF 2 α (ED 50 ) amounted 7.9 × 10 -6 M and 6.3 × 10 -6 M in the luteal and follicular phase, and 5.0 × 10 -6 M in early pregnancy. ED 50 for PGE 2 reached 5.0 × 10 -7 M in the luteal phase, and 4.1 × 10 -7 M in early pregnancy. For both prostaglandins, the contraction was much stronger (P < 0.01) in OA than in UA branches. In OA, the ED 50 for PGF 2 α was 1.2 × 10 -5 M in the luteal phase and was significantly higher (P < 0.05) than in the follicular phase (3.1 × 10 -6 M) and early pregnancy (2.7 × 10 -6 M). ED 50for PGE 2 amounted 7.3 × 10 -7 M in the luteal phase and 1.7 × 10 -7 M in early pregnancy. Studies showed the influence of the estrous cycle and early pregnancy on OA branches sensitivity to the contractile effect of PGF 2 α and the lack of this effect on UA branches, and the influence of the estrous cycle on UA and OA branch contraction in response to PGE 2 .

Loss of Function of Endothelin-2 Leads to Reduced Ovulation and CL Formation

“…Incorrect genotyping was ruled out and, in consideration of the established ability of EDN2 to induce contraction in ovarian tissues [13], [16], it is speculated that contraction might be induced in these Edn2KO ovaries by some molecules(s) such as prostaglandins that are produced in the ovary [42], [43], triggering oocyte expulsion. Both of these Edn2KO mice had low serum progesterone concentration, strengthening the assumption that EDN2 is necessary for CL formation even when oocyte release occurs.…”

Effects of Indomethacin on the Norepinephrine-Induced Contraction in Vascular Smooth Muscle during Different Stages of the Estrous Cycle

“…On the other hand, the norepinephrine constrictor response in the rat aorta, as well as its relationship with vascular biosynthesis of prostanoids, has also been studied (Zamorano et al, 1994). The effect of prostaglandins PGF2α and PGE2 has also been investigated in rats (Zamorano et al, 1995) and in other animals (Skipor et al, 2010). There is a close relationship between the contractility of the arteries and the production of PGs, especially during the estrous cycle (Skipor et al, 2010).…”

“…The effect of prostaglandins PGF2α and PGE2 has also been investigated in rats (Zamorano et al, 1995) and in other animals (Skipor et al, 2010). There is a close relationship between the contractility of the arteries and the production of PGs, especially during the estrous cycle (Skipor et al, 2010). There are also some studies on the influence of steroids on the norepinephrine-mediated contractile response (Zamorano et al, 1994;Ok et al, 2014).…”