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A possible role of the uterus in regulating content of luteal prostaglandins (PGs) was investigated. Pseudopregnancy was induced in adult virgin female rats by mating them with vasectomized male rats. On Day 5 of pseudopregnancy, decidualization of the uterus was induced or hysterectomy was performed. As controls, intact pseudopregnant animals with a luteal phase of 13 +/- 1 days were used. Measurements of in vivo tissue levels of PGF2 alpha, PGE2, and 6-keto-PGF1 alpha were performed by RIA after homogenization and extraction procedures in CL of pseudopregnancy and remainder of ovaries on Days 5, 13, and 19. Serum levels of progesterone and 20 alpha-dihydroprogesterone were determined by RIA. In hysterectomized animals, PGF2 alpha levels increased 2.5-fold in corpora lutea on Day 13 compared with levels on Day 5 of pseudopregnancy, but were still lower than in control rats undergoing functional luteolysis on Day 13. Decidual-tissue-bearing rats exhibited low levels of PGF2 alpha on Day 13 of pseudopregnancy. On Day 19, when luteolysis had occurred in decidual-tissue-bearing and hysterectomized rats, as judged by plasma levels of progestins, luteal content of PGF2 alpha was elevated to a similar level as that in control animals undergoing functional luteolysis on Day 13. When data pooled from control, decidual-tissue-bearing and hysterectomized rats were analyzed, a highly significant inverse correlation (r = -0.72, n = 46, p less than 0.001) between luteal PGF2 alpha content and ratio of plasma progestins was found.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Administration of exogenous prostaglandins at the time of mating may improve fertility via their effects on uterine contractility. The present study was undertaken to compare the effects of three prostaglandins that affect either the male or female reproductive uterine contractility. Contractions in the uterine body of anesthetized ewes during estrus were studied before, during and after a 5 min interval of systemic infusion of prostaglandin F2α-THAM salt (PGF2α; 5 mg), prostaglandin E1 (PGE1; 5 mg), prostaglandin E2 (PGE2; 5 mg) or vehicle. Pressure changes were detected by the use of an open-ended intrauterine catheter and a transducer. Each of the three prostaglandins initially caused a single prolonged contraction that lasted about 10 minutes and had a maximum pressure of 50 mm Hg. Prior to the prolonged contraction, PGE1 and E2 caused a relaxation for about 1 minute. In addition, PGE1 and E2 caused more secondary contractions (15–20) during the prolonged contraction than did PGF2α (7–9). The effects of prostaglandin (PG) treatment lasted for 20–30 minutes. The authors conclude that with the dose used the three prostaglandins studied do not have greatly different effects on uterine contractility in estrous ewes. 相似文献
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The length of pseudopregnancy and the progesterone levels in rats pseudopregnant and hysterectomized on their 2nd day and injected daily with indomethacin (500 g/0.2 ml) from the 2nd to 10th day do not differ from those exhibited by oil treated rats. On the contrary, indomethacin treatment from 11th day on, results in both a lengthening of the diestrous phase and a delayed luteolysis. These findings point out to an extrauterine prostaglandin synthesis mechanism participating in the functional luteolysis in histerectomized pseudopregnant rats. 相似文献
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Effects of prostaglandins on the production of collagenase by rabbit uterine cervical fibroblasts 总被引:3,自引:0,他引:3
Effects of prostaglandins on the production of collagenase by rabbit uterine cervical fibroblasts were investigated. Exogenous prostaglandin E2 (PGE2) and PGF2 alpha significantly stimulated the production of collagenase in a dose dependent manner, whereas PGI2 did not. Addition of arachidonic acid in the presence of absence of indomethacin to the cell culture did not show any increase in collagenase production. Recombinant human interleukin-1 (rhIL-1) also promoted the production of cervical collagenase independently of endogenous prostaglandin(s). Furthermore both exogenous PGE2 and PGF2 alpha enhanced the rhIL-1-induced collagenase production whereas PGI2 and/or indomethacin did not. These results suggested that exogenous PGE2 and PGF2 alpha but not endogenous prostaglandin(s) participate in cervical ripening and dilation by enhancing collagenase production by rabbit uterine cervical cells. 相似文献
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Arachis oil instilled into the uterus of sensitized mice was localized mesometrially or, more commonly, antimesometrially, suggesting that the uterus is polarized in its capacity to respond since implantation chambers only form antimesometrially. Epithelial breakdown occurred only within the 'implantation chabmer', but cell death took place more rapidly than in normal pregnancy and was complete at only 5 to 9 hr after the Pontamine Blue reaction. Between 19 and 43 hr after oil instillation, the antimesometrial epithelial cells lost contact with each other and initially were characterized by distended rough endoplasmic reticulum and Golgi body, lipid droplet accumulation and ribosome segregation. At a later stage of deterioration, epithelial cell contents were scattered into the uterine lumen where polymorphonuclear leucocytes and monocytes were also found, probably involved in ingesting the cellular debris. There was no evidence of increased size of lysosomal dense bodies or of the formation of autophagosomes in dying epithelial cells; suggesting that the mechanism of epithelial death in the oil-induced reaction is not identical to that of normal pregnancy. 相似文献
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Kenneth E. Clark June E. Austin Stanley J. Stys 《Prostaglandins & other lipid mediators》1981,22(3):333-348
The effects of the bisenoic prostaglandins on the uterine vasculature and uterine contractile activity have been evaluated in an unanesthetized chronically catheterized nonpregnant sheep preparation. Changes in uterine blood flow were monitored with electromagnetic flow probes while uterine contractile activity and tone were determined via an intra-uterine balloon connected to a pressure transducer. Prostaglandins A2, D2, E2, and prostacyclin (PGI2) were all found to be vasodilators. PGD2 and PGI2 were much more potent than PGA2 and PGE2 in dilating the uterine vasculature. The prostacyclin breakdown product 6-keto PGF1α, PGF2α, thromboxane B2, and the endoperoxide analogues U44069 and U46619 produced vasoconstriction of the uterine vasculature. Prostaglandins A2, D2 and F2α increased while PGI2 decreased uterine contractile activity. PGF2α also increased uterine tone suggesting that a portion of its vasoconstrictor activity may be due to mechanical compression of the uterine vasculature. 相似文献
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Plasma oestradiol concentrations did not change during hCG-induced pseudopregnancy except for a slight increase on Day 18. However, a marked decline was observed in tissue oestradiol on Day 3 whether expressed on the basis of tissue wet weight or protein. The lowest concentration was found at Day 6 but the Day 18 values were comparable to those of untreated controls. 相似文献
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The effects of ethanol on uterine sensitivity to induction of decidualization and deciduoma growth were determined. Rats were ovariectomized, given an oestrogen-progesterone regimen to optimize induction and growth of deciduoma and randomly assigned to one of three ethanol treatment groups: (i) days 1-4 (pre-induction/period of sensitivity), (ii) days 5-9 (post-induction/period of growth), (iii) days 1-9 (periods of sensitivity and growth); or to a control group not treated with ethanol (pair-fed to treated groups). Ethanol (0, 1, 2, or 4 g kg-1) diluted in water was administered by stomach tube on the days prescribed. Decidualization was induced in one uterine horn by intraluminal injection of sodium phosphate buffer. Uterine sensitivity and decidual growth were assessed as cornu weight. Blood alcohol concentrations were measured by gas chromatography. Alcohol treatment reduced uterine sensitivity, but increased deciduoma growth. Blood alcohol concentrations rose to 133 mg% at 30 min, remained high for 90 min and declined to 82 mg% at 120 min. Thus, blood alcohol concentrations sufficient to induce mild intoxication in humans suppressed uterine sensitivity to decidualization and enhanced deciduoma growth in rats. As all ovarian steroid hormone support was exogenous, the effects of ethanol on deciduoma induction and growth were not due to alterations in the hypothalamic-pituitary-ovarian axis. 相似文献
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R Sridaran G Gibori 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1986,183(3):328-332
To determine if the administration of dihydrotestosterone (DHT) suppresses serum progesterone concentrations in pseudopregnant rats and if so what role the decidua play in mediating this effect, two pellets (8 mg) of DHT were inserted under each ovarian bursa on Day 9 of pseudopregnancy in hysterectomized or intact rats with or without the decidua. The treatment induced within 24 hr a 50% decline in serum progesterone concentrations in decidua-bearing rats only; a further reduction was observed on Days 11 and 12. To further determine if the effect of DHT on serum progesterone concentrations is due to its effect on luteal luteinizing hormone (LH)-receptor content, rats were similarly treated on Day 9 and the capacity of corpora lutea to bind 125I-labeled human chorionic gonadotropin (hCG) on Day 12 in all three groups of rats was examined. DHT treatment had no effect on luteal LH-receptor content in any group. These results suggest that DHT is luteolytic in pseudopregnant rats only in the presence of the decidua and it is speculated that this effect is mediated by suppressing the decidual luteotropin. 相似文献
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T G Kennedy 《Biology of reproduction》1985,33(1):140-146
Previous studies in which prostaglandin (PG) production was inhibited for a limited time by the s.c. administration of indomethacin have suggested that PGs are involved in the initiation of decidualization as well as the growth and differentiation of decidual cells. To reduce PG production during decidualization, in the present study indomethacin was infused from Alzet osmotic minipumps into the uterine lumen of ovariectomized rats with uteri sensitized for decidualization. To determine the effect of route of indomethacin administration on decidualization, rats received a single s.c. injection of indomethacin or its vehicle, and unilateral intrauterine infusion of indomethacin or its vehicle, in a factorial experiment. The inhibitory effects on decidualization, as assessed 5 days later by uterine weights, were greatest when both treatments were combined. Prostaglandins E and F concentrations 24 and 48 h after the insertion of the pumps were lower in the indomethacin-infused horns, suggesting that the indomethacin reduced uterine PG production. By contrast, subcutaneously administered indomethacin reduced uterine PG concentrations at 24 h but not at 48 h. Prostaglandin E2 and PGF2 alpha alone or combined, infused with indomethacin into the uterine lumen of rats treated subcutaneously with indomethacin, overrode the inhibitory effects of indomethacin. The dose-response relationships between these PGs and decidualization did not differ. These data suggest that PGs are required during the growth and differentiation of decidual cells from endometrial stromal cells. 相似文献