Interaction of E Prostaglandins and Syntocinon on the Pregnant Human Myometrium

Brummer, Hilary C.

doi:10.1111/j.1471-0528.1971.tb00277.x

Cited by 49 publications

(18 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, for animals autopsied 10 min after oxytocin injection but not for animals killed 1-2 h later, the dose-response relationship between oxytocin and uterine luminal fluid accumulation was affected by treatment of the animals with indomethacin. Thus, these data support the proposal of Brummer (1971) and of Liggins ( 1973 ) that prostaglandins act synergistically with oxytocin. However, the magnitude of this interaction does not appear to be great.…”

Section: Discussionsupporting

confidence: 81%

“…and certain other rodents, the uteri ox~tocin; it has previously-been proposed that become distended with fluid on the afternoon of ~rost%landins may either mediate the effect of proestrus, but in early estrus, the cervices relax, oxytocin on the myometrium (Vane and Williams allowing the fluid to escape into the vagina and to 1973) or act synergistically with oxytocin to alter the outside (Long aIld Evans 1922;1939; "yometria' (Brummer 1971 ;Liggins 1973). Blandau 1945).…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Effect of oxytocin on estrogen-induced uterine luminal fluid accumulation in ovariectomized rats and the role of prostaglandins

Kennedy¹

1978

Can. J. Physiol. Pharmacol.

View full text Add to dashboard Cite

In estrogen-treated ovariectomized rats, uterine luminal fluid accumulation has been used as an indirect measure of cervical tone, with loss of luminal fluid being interpreted as indicating reduced tone. Since the recently reported ability of analogues of prostaglandins E2 and F2α to cause loss of luminal fluid might have resulted, not from reduced cervical tone, but from uterine contractions forcing fluid through constricted cervices, the effects of oxytocin, also a stimulator of myometrial activity, on luminal fluid accumulation were investigated. When ovariectomized rats, implanted 72 h previously with a Silastic capsule containing 17β-estradiol, were given a single injection of oxytocin and killed 1–2 h later, oxytocin, in a dose-dependent fashion, reduced uterine luminal fluid accumulation. For a supramaximal dose of oxytocin, this effect was seen within 15 min. In rats in which one uterine horn was ligated at the cervical end, fluid accumulation in the ligated horns did not differ significantly in control and treated rats, whereas in nonligated horns, oxytocin reduced the fluid accumulation, suggesting that loss of fluid occurred through the cervix rather than by reabsorption. Given twice daily for 3 days commencing immediately after the insertion of the estrogen-containing capsule, oxytocin had no effect on luminal fluid accumulation in horns ligated at the cervical end, indicating that oxytocin did not inhibit luminal fluid formation. Prostaglandin biosynthesis did not appear to be essential for the acute effect of oxytocin since treatment of rats with indomethacin, although reducing uterine and cervical prostaglandin levels, did not inhibit the effect of oxytocin. However, loss of fluid occurred slightly sooner following oxytocin administration in controls than in indomethacin-treated animals. In addition, for animals autopsied 10 min after oxytocin injection, the dose–response relationship between oxytocin and uterine luminal fluid was affected by indomethacin treatment. These data suggest that prostaglandins act synergistically with oxytocin to bring about loss of uterine luminal fluid accumulation. However, the validity of the use of luminal fluid accumulation as an indicator of cervical tone remains to be resolved.

show abstract

Section: Discussionsupporting

confidence: 81%

Section: Introductionmentioning

confidence: 97%

Effect of oxytocin on estrogen-induced uterine luminal fluid accumulation in ovariectomized rats and the role of prostaglandins

Kennedy¹

1978

Can. J. Physiol. Pharmacol.

View full text Add to dashboard Cite

show abstract

“…The prostaglandins so produced would then potentiate the contraction induced by oxytocin, perhaps by increasing the rate and spread of depolarization as suggested by Aiken & Vane, 1971;1973;Ferreira, Moncada & Vane, 1973). If the capacity of the uterus to synthesize prostaglandins increases towards the end of pregnancy (see below) this would help to explain the progressive increase in sensitivity of the pregnant human uterus to oxytocin (Caldeyro-Barcia & Sereno, 1961;Brummer, 1971). However, our failure to modify the action of oxytocin on the pregnant rat uterus with indomethacin would suggest that such an effect is not attributable to a gradual and progressive change in uterine prostaglandin production.…”

Section: Discussionmentioning

confidence: 99%

The contribution of prostaglandin production to contractions of the isolated uterus of the rat

Vane

Williams

1973

British J Pharmacology

190

View full text Add to dashboard Cite

Summary1. Indomethacin and meclofenamate, both of which are potent inhibitors of prostaglandin synthetase, antagonized the contractor effects of oxytocin on the isolated uterus from the non-pregnant rat. Contractions induced by acetylcholine or prostaglandin F2a were not antagonized.2. Uteri from rats 17-22 days pregnant exhibited intermittent spontaneous contractions when used as isolated preparations. They also released prostaglandin-like activity (mainly similar to F2a) into the bathing fluid. Both the prostaglandin release and the uterine activity were abolished by indomethacin. Activity could be restored by addition of low concentrations of prostaglandin E2 or F2a.3. The release of prostaglandin F2a-like activity by the uteri increased dramatically on the expected day of delivery (day 22). 4. The results add force to the hypothesis that the spontaneous activity of some isolated organs is due to an intramural prostaglandin generation, and that increased uterine prostaglandin production contributes to the expulsion of the foetus.

show abstract

“…(1) The linoleic acid made available by DLL is converted to a prostaglandin which in turn sensitizes the pregnant rabbit uterus to oxytocin. Linoleic acid is a precursor of prostaglandins E 2 and F 2a [12], and certain prostaglandins increase myometrial activity [2,4] and sensitivity to oxytocin in the pregnant uterus [1]. (2) DLL in some way reduces the amount of progesterone available to maintain the pregnancy.…”

Section: Discussionmentioning

confidence: 99%

Premature Induction of Labor with Dilinoleyl Lecithin in Rabbits

1972

View full text Add to dashboard Cite

ExtractDilinoleyl lecithin (DLL), identified as a component of a crude mixture of soya bean phospholipids (SBP), was obtained in highly pure form by synthesis. The DLL was administered to 25-day pregnant rabbits in doses of 1.0 and 2.0 g/rabbit. One unit of oxytocin was administered intramuscularly 24, 48, and 49 hr after infusion, and the rabbits were observed for abortion. The abortion rate after the 1.0-g dose of DLL was 56.9 ± 6.9% and that after the 2.0-g dose was 100.0 ± 0%; the rate in controls was 2.6 ± 2.6%. Speculation

show abstract

Interaction of E Prostaglandins and Syntocinon on the Pregnant Human Myometrium

Cited by 49 publications

References 9 publications

Effect of oxytocin on estrogen-induced uterine luminal fluid accumulation in ovariectomized rats and the role of prostaglandins

Effect of oxytocin on estrogen-induced uterine luminal fluid accumulation in ovariectomized rats and the role of prostaglandins

The contribution of prostaglandin production to contractions of the isolated uterus of the rat

Premature Induction of Labor with Dilinoleyl Lecithin in Rabbits

Contact Info

Product

Resources

About