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1.
Bovine gastric mucosal and muscle microsomes synthesize prostaglandins and thromboxane b/ (TXB2) from aratchidonic acid (AA). TXB2 and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were the majro products synthesized by pylorus, body, and cardiac region of the gastric mucosa. Gastric muscle mainly synthesized 6-keto-PGF1 alpha. TXB2 and 6-keto-PGF1 alpha synthesis occurs at an appreciable rate from endogenous precursors but more rapidly with added arachidonate. Prostaglandins E2, F2 alpha and D2 were synthesized in smaller amounts under the conditions studied. 相似文献
2.
Iwao Koyama Haruo Yamagami Toyoyasu Kuwae Munetsugu Kurata 《Prostaglandins & other lipid mediators》1982,23(6):777-785
The release of 6-keto-prostaglandin F1α (6KF1α)_and of thromboxane B2 (TXB2) from cells were investigated using mouse peritoneal exudate cells (PECs) and non-cultured peritoneal macrophages. They were prepared by adhesion to glass dishes and incubated for 1 hr at 37°C in 5% Co2 in air. Both the percentage of spreading macrophages and the release of 6KF1α and TXb2 increased in proportion to the incubation time. 6KF1α and TXB2 were released from the macrophages, not from the non-adherent cells. When PECs were incubated in silicon-coated glass dishes, the spreading of macrophages was hardly detected and lower amounts of 6KF1α and TXB2 were released from these cells compared with cells incubated in non-treated glass dishes. These findings suggest that adhesion with the correlated spreading of macrophages on glass dishes serve as a considerable physical factor for the release of 6KF1α and TXB2. 相似文献
3.
The present study has been performed to investigate how PGs would participate the hatching process. Effects of indomethacin, an antagonist to PGs biosynthesis, on the hatching of mouse blastocysts were examined in vitro. Furthermore, it was studied that prostaglandin E2 (PGE2), prostaglandin F2α (PGF2α) or 6-keto-prostaglandin F1α (6-keto-PGF1α) were added to the culture media with indomethacin. (1) The hatching was inhibited by indomethacin yet the inhibition was reversible. (2) In the groups with indomethacin and PGE2, no improvement was seen in the inhibition of hatching and the inhibition was irreversible. (3) In the groups with indomethacin and PGF2α, inhibition of hatching was improved in comparison with the group with indomethacin. (4) In the groups with indomethacin and 6-keto-PGF1α, no improvement was seen. The above results indicated that PGF2α possibly had an accelerating effect on hatching and a high concentration of PGE2 would exert cytotoxic effect on blastocysts. 相似文献
4.
In humans eicosapentaenoic acid can be converted to 3-series prostaglandins (PGF3α, PGI3, and PGE3). Whether 3-series prostaglandins can protect the gastric mucosa from injury as effectively as their 2-series analogs is unknown. Therefore, we compared the protective effects of PGF3α and PGF2α against gross and microscopic gastric mucosal injury in rats. Animals received a subcutaneous injection of either PGF3α or PGF2α in doses raning from 0 (vehicle) to 16.8 μmol/kg and 30 min later they received intragastric administration of 1 ml of absolute ethanol. Whether mucosal injury was assessed 60 min or 5 min after ethanol, PGF3α was significantly less protective against ethanol-induced damage than PGF2α. These findings indicate that the presence of a third double bond in the prostaglandin F molecule between carbons 17 and 18 markedly reduces the protective effects of this prostaglandin on the gastric mucosa. 相似文献
5.
Urinary excretion of 6-keto-PGF1α was measured by high pressure liquid chromatography and radioimmunoassay at various stages of pregnancy and labor. In the first trimester of pregnancy, urinary 6-keto-PGF1α concentrations were nor different from those measured before pregnancy, but they showed a significant increase in the second trimester of pregnancy (p <0.001). The levels rose further in the third trimester, although this increase was not statistically significant when compared to levels obtained in the second trimester. There was no evidence for a significance change in 6-keto-PGF1α excretion with the onset of labor. During well-established, progressive labor mean values of 6-keto-PGF1α excretion were about twice as high as before the onset of labor, but the range of values during labor was so wide that there was no statistical difference with values obtained in the second half of pregnancy.It is concluded that the increase in the urinary excretion of 6-keto-PGF1α occurs later in pregnancy than the increase in TXB2 excretion and that labor at term is not associated with marked changes in 6-keto-PGF1α excretion. 相似文献
6.
Shiro Ohki Yoshimasa Nishigaki Katsuhiro Imaki Masayasu Kurono Fumio Hirata Toshio Hanyu Nobuhiko Nakazawa 《Prostaglandins & other lipid mediators》1976,12(2):181-186
Radioimmunoassay technique for measuring 5α,7α-dihydroxy-11-keto-tetranorprosta-1,16-dioic acid, the main urinary metabolite of PGF1α and PGF2α (PGF2α-MUM), was further improved.It was postulated based on some experimental data that the PGF2α-MUM exists in the urine mostly as dioic acid form, not as δ-lactone formThe daily excretion of PGF2α-MUM in men ranged from 14.43 μg to 36.14 μg and in women from 5.21 μg to 14.25 μg. 相似文献
7.
Burkhard Scherer Sven Fischer Wolfgang Siess Peter C. Weber 《Prostaglandins & other lipid mediators》1982,23(1):41-52
A radioimmunoassay (RIA) for the estimation of 6-keto-PGF1α in human urine is described in detail. The RIA method was validated by direct comparison to gas chromatography-mass spectrometry. In adults and in one year old children basal excretion of 6-keto-PGF1α was found to be lower than that reported for PGE2 or PGF2α. However, during the first week of life, significantly more 6-keto-PGF1α was excreted. The very high levels of 6-keto-PGF1α in urine seen on the third day of life seemed already to decrease during the first week of life. It is concluded that prostacyclin may have a major role for kidney function in the newborn, possibly by protecting the immature kidney from high levels of angiotensin II. 相似文献
8.
Michael C. Koss 《Prostaglandins & other lipid mediators》1976,12(6):997-1004
Prostaglandin F2α (5μg/kg, i.v.) causes an increase in pulmonary arterial pressure, decrease in systemic arterial pressure, and reflex bradycardia in the anesthetized cat. The same dose of the 15-methyl analogue of PGF2α produces the same triad of effects but of greater magnitude and duration. Although prostaglandins F1α, F2β and F1β also cause the same cardiovascular effects as F2α, there is a decrease in potency for all parameters measured, with PGF2α>PGF1α>PGF2β>PGF1β. When compared to the actions of PGF2α in producing an increase in pulmonary arterial pressure, PGs F1α, F2β and F1β were less potent by approximately 10, 100, and 1000 fold respectively. 相似文献
9.
G.C. Liggins G.A. Campos C.M. Roberts S.J. Skinner 《Prostaglandins & other lipid mediators》1980,19(3):461-477
Human endometrium obtained from fresh hysterectomy specimens was perifused for 7 hr in 95% O2/5% CO2 at 37°C. The phase of the menstrual cycle was determined by histological examination. The concentrations of PGF, 6-keto-PGF1α and TxB2 in 20 min fractions of the perifusion medium were measured by radioimmunoassay and production rates were calculated in terms of dry weight of tissue. Biphasic patterns of production were observed; high initial values fell to about 20% at 2 hr and then increased to relatively stable values at about 4 hr which were maintained for the next 2 hr. During this latter period, production rates in endometria taken at different phases of the cycle differed markedly from each other; the production rates of PGF in secretory and early proliferative endometria were low (15.8 ± 2.6, mean ± SEM and 67.2 ± 8.3 ng/min/g respectively) whereas they were high in late proliferative and premenstrual endometria (188.0 ± 16.7 and 196.4 ± 16.9 ng/min/g respectively). The patterns of production of 6-keto-PGF1α and TxB2 were similar to those of PGF but the absolute values were much lower (<10%). We conclude that the observed rates of production of prostaglandins by perifused human endometrium are consistent with synthesis being stimulated either by estrogen or withdrawal of hormonal support and being inhibited by progesterone. 相似文献
10.
PGI2 and 6-keto-PGF1α were converted to 6-methoxime-PGF1α (6-MeON-PGF1α) by treatment with methoxyamine HCl in acetate buffer. The formed 6-MeON-PGF1α was measured by radioimmunoassay. Antisera were raised in rabbits after immunization against 6-MeON-PGF1α-BSA conjugate. Diluted 1:20.000 to bind 50% of the tracer (3H-6-MeON-PGF1α, 100 Ci/mmol), the antiserum cross reacted 0.8% with PGE2, 1% with PGF2α and less than 0.2% with PGD2, PGF1α, PGF2β and TXB2. The radioimmunoassay was used to estimate release of PGI2 and 6-keto-PGF1α from chopped rabbit renal medulla and cortex incubated in Krebs-Ringer bicarbonate buffer (37°C, 30 min). The 6-keto-PGf1α radioimmunoassay was validated in biological samples by mass fragmentography. The chopped medulla (n=5) released 38±9 ng/g/min and the cortex (n=5) 4.7±2.0 ng/g/min, while the release of immunoreactive PGE2 (iPGE2) and iPGF2α was 171±26 and 74±13 ng/g/min from the medulla and 4.3±1.3 and 2.7±0.3 ng/g/min from the cortex, respectively. The results confirm previous findings, which indicate that in the renal medulla prostaglandin endoperoxides are mainly transformed to prostaglandins, while in the cortex transformation to PGI2 seems to be of greater
importance. 相似文献
11.
Claudia Weber Michael Hller Johan Beetens Fred De Clerck Frank Tegtmeier 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,562(1-2)
A method for quantification of 6-keto-PGF1α, 2,3-dinor-6-keto-PGF1α, TXB2, 2,3-dinor TXB2, PGE2, PGD2 and PGF2α in human urine samples, using gas chromatography—negative ion chemical ionization mass spectrometry, is described. Deuterated analogues were used as internal standards. Methoximation was carried out in urine samples which were subsequently applied to phenylboronic acid cartridges, reversed-phase cartridges and thin-layer chromatography. The eluents were further derivatized to pentafluorobenzyl ester trimethylsilyl ethers for final quantification by gas chromatography—mass spectrometry. The overall recovery was 77% for tritiated 6-keto-PGF1α and 55% for tritiated TXB2. Urinary levels of prostanoids were determined in a group of six volunteers before and after intake of the thromboxane synthase inhibitor Ridogrel, and related to creatinine clearance. 相似文献
12.
Norman A. Nelson R.W. Jackson Oldrich K. Sebek 《Prostaglandins & other lipid mediators》1978,16(1):85-92
This paper reports the synthesis of 11-dehydrothromboxane B2 methyl ester (II), 15-dehydrothromboxane B2 methyl ester (III), 15-dehydro-13,14-dihydrothromboxane B2 (XII) and 2,3-dinorthromboxane B2 methyl ester (XV). These compounds, as their free acids, have been reported to be thromboxane metabolites. 相似文献
13.
F. Cottee R.J. Flower S. Moncada J.A. Salmon J.R. Vane 《Prostaglandins & other lipid mediators》1977,14(3):413-423
At low substrate/enzyme ratios, and in the absence of reduced glutathione (GSH), the major prostaglandin (PG) biosynthesised by the ram seminal vesicle cyclo-oxygenase from arachidonic acid was 6-keto-PGF1α. The addition of nanomolar amounts of reduced GSH suppressed biosynthesis of this product and stimulated the formation of PGE2; 1-epinephrine enhanced the conversion of the substrate but had not effect on the type of product formed. 15-Hydroperoxy arachidonic acid selectively inhibited formation of 6-keto-PGF1α (IC50 100 μM) but blocked synthesis of all cyclooxygenase products at concentations greater than 1 mM. At substrate concentrations of 30 μM or greater, synthesis of 6-keto-PGF1α was inhibited and PGE2 and PGF2α were the main products formed. 相似文献
14.
Anna-Riitta Fuchs Peter Husslein Linda Sumulong Fritz Fuchs 《Prostaglandins & other lipid mediators》1982,24(5):715-722
All uterine tissues as well as the fetal membranes and the placenta can form prostaglandins from endogenous precursors
but it is not clear which of the tissues is the main site for the increase in PGF2α production during human parturition. To examine this question, we measured plasma prostaglandin levels before and at intervals after expulsion of the fetus, placenta, and membranes. The concentration of PGFM at the beginning of the second stage of labor was significantly higher than before the onset of labor. Five minutes after the birth of the infant, the concentration had doubled. Thirty minutes after the expulsion of placenta and membranes, plasma PGFM had fallen to the levels at full dilatation; two hours postpartum it was still significantly raised over levels before labor. Since the halflife of PGFM in the circulation is about 7 minutes, these findings indicate that the uterine tissues are important sources of PGFM during labor. In contrast, endogenous oxytocin levels, which were significantly raised over control levels at the second stage of labor, did not change during the third stage, and decline postpartum to control levels. Oxytocin infusion did not influence PGFM levels at 5 and at 30 minutes postpartum, but raised them at 2 hours. 相似文献
15.
The effect of six naturally occurring prostaglandins on isolated umbilical arteries and veins has been studied. All six prostaglandins had a constricting effect on the umbilical vessels. On the umbilical artery preparations the potencies in decreasing order were A2>B2>F2α>B1>E2>A1. Prostaglandin B2 was more potent than PGA2 on the umbilical vein. Polyphloretin phosphate (PPP) antagonised the constricting effect of all six prostaglandins without altering responses to 5-hydroxytryptamine. 相似文献
16.
L.A. Reichard H.D. Hafs N.B. Haynes R.J. Collier T.E. Kiser M.S. McCarthy 《Prostaglandins & other lipid mediators》1978,16(1):135-142
Two experiments were conducted, the first to compare sperm output and the second to determine serum testosterone in rabbits given PGF2α or PGE2. In the first, six rabbits were ejaculated twice each Monday, Wednesday and Friday for 5 weeks. Each rabbit was given subcutaneously (sc) each of the following treatments five times: 1) saline, 2) 5 mg PGF2α and 3) 5 mg PGE2. Treatments were given, half at 4 hr and half at 2 hr before first ejaculations. Both PGF2α and PGE2 caused increased (50% and 84%) sperm content of first ejacula, without significantly altering characteristics of second ejacula. The extra sperm in first ejacula was a function of increased sperm density, because seminal volume was unaltered.In the second experiment, 15 rabbits were bled at 0.5-hr intervals for 9 hr and given (sc): 1) saline at 1 and 3 hr (n=4), 2) 2.5 mg PGF2α at 1 and 3 hr (n=4), 3) 2.5 mg PGE2 at 1 and 3 hr (n=4) or 4) 5 mg PGF2α at 1 hr after the onset of blood sampling. In saline-treated controls, episodic surges of testosterone occurred on the average every 5 hours. After the injection of 2.5 or 5.0 mg PGF2α, serum testosterone began to rise at 0.5 hr, peaked (8 to 13 ng/ml) at 1 hr and approached a nadir (0.5 ng/ml) within 4 hours. The second injection of 2.5 mg PGF2α failed to significantly affect serum testosterone. PGE2 treatment was followed by significantly depressed serum testosterone; only 1 of these 4 rabbits had any surge of testosterone for the 8 hr after treatment. In conclusion, PGF2α and PGE2 both increased sperm output, but PGF2α increased serum testosterone while PGE2 depressed serum testosterone. Thus, the sperm output effect of these prostaglandins probably is independent of the acute changes in testosterone secretion. 相似文献
17.
The amount of free arachidonic acid and prostaglandin F2α in rat cerebral hemispheres was increased following convulsions induced by carbachol and metrazol. The level of thromboxane B2 was not affected and prostaglandin endoperoxides could only be “trapped” after a very short convulsive period. Unesterified fatty acid levels at 2 minutes post-mortem were decreased by 50% in the cerebral hemispheres of phenytoin treated rats. Under the same conditions, phenobarbital and diazepam had little effect on the levels of free fatty acids in rat brain. 相似文献
18.
Shiro Ohki Katsuhiro Imaki Fumio Hirata Toshio Hanyu Nobuhiro Nakazawa 《Prostaglandins & other lipid mediators》1975,10(6):549-555
Radioimmunoassay of 5α,7α-dihydroxy-11-keto-tetranorprosta-1,16-dioic acid, main urinary metabolite of prostaglandin F2α (PGF2α), was performed using an antiserum produced in the rabbit.The antibody in 100 μ1 of 1,600-fold diluted antiserum binds with 60 picograms of metabolite.The main urinary metabolite level fell when flufenamic acid, a prostaglandin synthetase inhibitor, was given to rats. In contrast, it was significantly elevated when PGF2α was administered. 相似文献
19.
Prostaglandin (PG)F2α, E2, D2 and 6-keto-F1α were determined in human cerebrospinal fluid by a mass spectrometric technique. The samples were obtained from 12 patients with suspected intracranial disease. A 64 fold variation in PG levels was observed. The major PG was 6-keto-F1α (0.12–15 ng/ml). PGF2α and PGE2 were present in lower concentrations PGD2 was below the level of detection (0.05 ng/ml) except in one patient with extremely high total levels of PGs. 相似文献
20.
Jerome M. Feldman James W. Plonk James C. Cornette 《Prostaglandins & other lipid mediators》1974,7(6):501-506
Using specific radioimmunoassay procedures we measured prostaglandin F2α (PGF2α) and 13, 14-dihydro-15-keto prostaglandin F2α (PGF2α metabolite) in 12 patients with carcinoid tumors. Although PGF2α and PGF2α metabolite were each modestly elevated in 17% of the patients the magnitude of the elevation did not correlate with the symptoms of the carcinoid syndrome. The 24 hour urinary 5-hydroxyindoleacetic acid excretion showed a good correlation with carcinoid symptoms while the serum serotonin concentration showed a fair correlation with carcinoid symptoms. We conclude that serum elevation of PGF2α is not a frequent occurrence in patients with the carcinoid syndrome. 相似文献