Poly I:C accelerates ovum transport in the rabbit by a prostaglandin-mediated mechanism

Abstract

Administration of poly I:C (1 mg/kg i.v.) to rabbits 24 h after an ovulating injection of hCG caused accelerated ovum transport; only 30% of the ova were still found in the oviducts 24 h later compared with 79% of ova in control animals. This action of poly I:C was prevented by concomitant administration of indomethacin. Poly I:C (0.5 mg/kg i.v.) given to anaesthetized rabbits produced significantly increased levels of prostaglandins (PGs) E and F in uterine vein blood up to 2 h later. Production of PGs by lung, oviduct and myometrium was unaffected 2 h after poly I:C administration, but production of both PGE and PGF by endometrium was significantly elevated at the same time. Metabolism of PGs by cytosols of lung, oviduct and uterus was inhibited to various degrees at 2 h after poly I:C (1 mg/kg i.v.), but by 4 h after treatment this process was reduced to 70--80% of pretreatment values. It is concluded that poly I:C accelerates ovum transport through the oviduct by a PG-mediated mechanism, and that elevated levels of PGs in oviduct are due to inhibition of metabolism of PGs.

Effects of Epostane on Ovarian Levels of Progesterone, 17β-Estradiol, Prostaglandin E2, and Prostaglandin F2α during Ovulation in the Gonadotropin-Primed Immature Rat*

“…The prostanoid RIAs were performed by direct assay of the supernatant fluid according to procedures previously described (5). The prostaglandin E 2 assay had a cross-reactivity of 50% with prostaglandin Ei, 6.0% with prostaglandin A 2 , 3.0% with prostaglandin A l5 1.3% with prostaglandin F 2a , and less than 1.0% with other common prostanoids.…”

Cycloheximide inhibition of ovulation, prostaglandin biosynthesis and steroidogenesis in rabbit ovarian follicles

“…(In no instance were the samples stored for longer than 3 weeks.) The RIAs were performed according to procedures described elsewhere (Harper et al, 1981). Although the antibodies were produced by innoculating rabbits with PGE-2 and PGF-2a, the results are expressed simply as PGE and PGF because the antibodies cross-react essentially 100% with PGE-1 and PGF-la, respectively.…”

Human endometrial epithelial cells grown on collagen in serum-free medium. Estrogen responsiveness and morphology

“…PGF2a was assayed by radioimmunoassay (14) and the results are given as ng/well x 24 h. Progesterone in the serum samples was assayed in a routine radioimmunoas¬ say (15).…”