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1.
Prostaglandin (PG)F, E2, D2 and 6-keto-F 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-F (0.12–15 ng/ml). PGF 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   

2.
A method for quantification of 6-keto-PGF, 2,3-dinor-6-keto-PGF, TXB2, 2,3-dinor TXB2, PGE2, PGD2 and PGF 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-PGF 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   

3.
Reactions of [CpCo(PPh3)2](Cp=η5-cyclopentadienyl) with conjugated diacetylenes were investigated in terms of the synthesis of π-conjugated organometallic polymers. The reaction of an α,β-diyne, PhCC---CCPh, gave three geometric isomers of dialkynylcobaltacyclopentadienes, 1a-c, and an insoluble polymeric product, 1d. A 2,4-dialkynyl complex, 2, and a 2,5-dialkynyl complex, 3, were obtained solely from Me3SiCC---CCSiMe3 and MeCC---CCMe, respectively. 1,1′-Bis(trimethylsilylethynyl)-4,4′-biphenyl afforded two isomers of 1,3-dialkynylcyclobutadiene complexes, 4a and 4b. The stability of the one-electron oxidized forms of the cobalacyclopentadiene and cyclobutadiene complexes was examined by cyclic voltammetry.  相似文献   

4.
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 F (PGF) or 6-keto-prostaglandin F (6-keto-PGF) 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 PGF, inhibition of hatching was improved in comparison with the group with indomethacin. (4) In the groups with indomethacin and 6-keto-PGF, no improvement was seen. The above results indicated that PGF possibly had an accelerating effect on hatching and a high concentration of PGE2 would exert cytotoxic effect on blastocysts.  相似文献   

5.
Dietary supplementation with a fish oil concentrate (FOC) reduced the endogenous synthesis of prostacyclin (PGI2), as measured by the excretion of its major urinary catabolite, 2,3-dinor-6-oxo-PGF (PGI2-M). Thirty-four healthy men (24–57 years old) were given controlled diets and supplements that provided 40% of the energy from fat and a minimum of 22 mg/d of α-tocopherol for two consecutive experimental periods of 10 weeks each. During the experimental periods, the men received capsules containing 15 g/d of a placebo oil (PO) (period 1) or 15 g/d of the FOC (period 2). In addition to the PO or FOC, capsules contained 1 mg of α-tocopherol per g of fat as an antioxidant. The average daily excretion of PGI2-M during the last week of FOC supplementation (period 2) was 22% less (P = 0.0001) than at the end of the first period. These results are at variance with those reported in comparable human studies conducted by other investigators during the middle and late 1980s. A 20% reduction (P = 0.003) in the 11-dehydrothromboxane B2 to 2,3-dinor-6-oxo-PGF excretion ratio at the end of period 2 in this study demonstrates that a shift of the n-6 to n-3 polyunsaturated fatty acid ratio from 12.5 to 2.3 brings about a substantial modulation of the eicosanoid system.  相似文献   

6.
Formation of {3H}-PGF and {3H}-13,14,dihydro-15-keto-PGF from {3H}-PGE2 by the supernatant of uterine homogenates from estrous and ovariectomized rats, was studied, using the reaction system PGE2 + NADPH + {3H}-PGE2 + supernatant. Enzymatic conversion was lower in uterine supernatants from spayed rats than in uterine homogenates of rats at natural estrus.Spayed animals were injected with progesterone (P) or with estradiol-17-β (E0) at a dose of 1.0 or 50.0 ug. Conversion of {3H}-PGF to {3H}-PGE2 or to {3H}-13,14,dihydro-15-keto-PGF did not differ in control ovariectomized or ovariectomized rats receiving P or 1.0 ug E0. However, 50.0 ug E0 induced a significant oversion after 30 (P < 0.01) and 60 (P < 0.001) min of incubation.It is concluded that E0, at the 50.0 ug dose, but not the 1.0 ug dose of E0, nor progesterone, stimulated conversion of {3H}-PGE2 into {3H}-PGF or {3H}-13, 14,dihydro-15-keto-PGF, presumably through the activity of the enzyme PGE2-9-keto-reductase.  相似文献   

7.
PGI2 and 6-keto-PGF were converted to 6-methoxime-PGF (6-MeON-PGF) by treatment with methoxyamine HCl in acetate buffer. The formed 6-MeON-PGF was measured by radioimmunoassay. Antisera were raised in rabbits after immunization against 6-MeON-PGF-BSA conjugate. Diluted 1:20.000 to bind 50% of the tracer (3H-6-MeON-PGF, 100 Ci/mmol), the antiserum cross reacted 0.8% with PGE2, 1% with PGF and less than 0.2% with PGD2, PGF, PGF and TXB2. The radioimmunoassay was used to estimate release of PGI2 and 6-keto-PGF from chopped rabbit renal medulla and cortex incubated in Krebs-Ringer bicarbonate buffer (37°C, 30 min). The 6-keto-PGf 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 iPGF 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   

8.
Plasma prolactin and F-prostaglandins (PGF) were measured in anesthetized male Sprague-Dawley rats before and at 15, 30, 45 and 60 minutes following i.v. injection of either PGF (4 mg/kg), chlorpromazine, 1 mg/kg or chlorpromazine (1 mg/kg) after pretreatment with i.p. indomethacin (2 mg/kg). Following PGF administration, plasma prolactin levels increased significantly only at 15 and 30 minutes in spite of extremely high PGF levels throughout 60 minutes. Besides the expected rise in plasma prolactin, chlorpromazine caused a transient but statistically significant increase in PGF. Indomethacin blocked the chlorpromazine-induced PGF rise but not prolactin increase. Animals stressed with ether anesthesia showed elevation of plasma prolactin, which was not blocked by indomethacin although PGF concentration fell. These results indicate that PGF can stimulate prolactin release. This effect does not appear to be physiologic since very high PGF levels are required. Furthermore, blockade of prostaglandin synthesis by indomethacin does not prevent the release of prolactin in response to chlorpromazine or stress. Our findings do not support a possible role of PGFs as intermediaries in prolactin release. However, it is possible that PGFs may work through other mechanisms not investigated in our study.  相似文献   

9.
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   

10.
Medical or surgical castration for the treatment of prostatic cancers prevents androgen production by the testes, but not by the adrenals. Inhibition of the key enzyme for androgen biosynthesis, cytochrome P45017α, could prevent androgen production from both sources. The in vivo effects of 17-(3-pyridyl)androsta-5,16-dien-3β-ol (CB7598) and 17-(3-pyridyl)androsta-5,16-dien-3-one (CB7627), novel potent steroidal inhibitors of this enzyme, on WHT mice were compared with those of castration and two clinically active compounds, ketoconazole and flutamide. Flutamide and surgical castration caused significant reductions in the weights of the ventral prostate and seminal vesicles. CB7598, in its 3β-O-acetate form (CB7630), and CB7627 caused significant reductions in the weights of the ventral prostate, seminal vesicles, kidneys and testes when administered once daily for 2 weeks. Ketoconazole, given on the same schedule, caused no reductions. Plasma testosterone was reduced to 0.1 nM by CB7630, despite a 3- to 4-fold increase in the plasma level of luteinizing hormone. Adrenal weights were unchanged following treatment with CB7630 or CB7627 but were markedly increased following ketoconazole, indicating no inhibition of corticosterone production by these steroidal compounds. These results indicate that CB7598, CB7630 or CB7627 may be useful in the treatment of hormone-dependent prostatic cancers.  相似文献   

11.
Our reported data on the cortical inhibitory actions of prostaglandin F (PGF) and the diversity of data in the literature on cerebral PG actions are examined here in the light of intracellular recording which provides the requisite membrane data for the first time. Thus, 1) intracellular recording from the cat cerebral cortex is obtained for the actions of PGF and for norepinephrine (NE) and serotonin (5HT). 2) The parallel changes in firing and polarization and the simultaneous transmembrane conductance changes are qualitatively identical for PGF, NE and 5HT. 3) The reduction in firing accompanied by hyperpolarization indicates that PGF, NE and 5HT all inhibit these cells. 4) The ionic species responsible for this inhibition is such that it increased the transmembrane resistance, and this was true for all three. 5) The changes in membrane parameters, identical in direction for PGF and NE, but stronger for the latter, constitute conditions that can lead to competitive inhibition and therefore conote, presumably, actions at the same or related receptors. Such competition with evoked cortical field potentials is shown in the preceding paper.  相似文献   

12.
The improved methods for the preparation of valency hybrid hemoglobins, (α3+β2+)2 and (α2+β3+)2 were presented. The (α3+β2+)2 valency hybrid was separated from the solutions of partially reduced methemoglobin with ascorbic acid, by using CM 32 column chromatography. The (α2+β3+)2 valency hybrid was also isolated from hemoglobin solutions, which were partially oxidized with ferricyanide, by chromatography on CM 32 column. These valency hybrid hemoglobins were found to be single on isoelectric focusing electrophoresis. Present procedures are very simple and are suitable for the bulk preparation of (α3+β2+)2 and (α2+β3+)2 valency hybrids.  相似文献   

13.
In humans eicosapentaenoic acid can be converted to 3-series prostaglandins (PGF, 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 PGF and PGF against gross and microscopic gastric mucosal injury in rats. Animals received a subcutaneous injection of either PGF or PGF 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, PGF was significantly less protective against ethanol-induced damage than PGF. 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   

14.
The new organometallic cluster (η24-CO)2(CO)136-C6Me6) has been prepared by the thermolysis of Ru3(CO)12 with hexamethylbenzene in octane and characterised by a single crystal X-ray diffraction study. It is isostructural with the known cluster Ru624-CO)2(CO)136-C6H3Me3) and the metal core constitutnts the same tetrahedral Ru4 unit with two edge-bridging Ru atoms. The mesitylene derivative has been shown to undergo rearrangement to afford the octahedral carbido cluster Ru6C(CO)146-C6H3Me3), but this conversion is not observed for the new hexamethylbenzene derivative.  相似文献   

15.
Hapten derivatives of 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3 were synthesized using the Wittig–Horner approach. Both haptens bearing a carboxylic group at the side chain that can be linked to a protein for raising antibodies of potential utility for the determination of 25-hydroxyvitamin D3, 1α,25-dihydroxyvitamin D3 and 1α-hydroxylated vitamin D3 analogues.  相似文献   

16.
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   

17.
Radioimmunoassays for measuring prostaglandin F (PGF) and 5α, 7α-dihydroxy-11-keto tetranorprosta-1,16-dioic acid, PGF-main urinary metabolite (PGF-MUM), with 125I-tyrosine methylester amide (TMA) of PGF and PGF-MUM were developed.Antibody to PGF was produced in rabbits immunized with conjugates of PGF coupled to bovine serum albumine. Antibody to PGF-MUM was also produced in rabbits immunized with conjugates of PGF-MUM coupled to bovine serum albumin.PGF-125I-TMA had an affinity to antiserum to PGF. PGF-MUM-125I-TMA also responded to antiserum to PGF-MUM.  相似文献   

18.
An α- -fucosidase from porcine liver produced α- -Fuc-(1→2)-β- -Gal-(1→4)- -GlcNAc (2′-O-α- -fucosyl-N-acetyllactosamine, 1) together with its isomers α- -Fuc-(1→3)-β- -Gal-(1→4)- -GlcNAc (2) and α- -Fuc-(1→6)-β- -Gal-(1→4)- -GlcNAc (3) through a transglycosylation reaction from p-nitrophenyl α- -fucopyranoside and β- -Gal-(1→4)- -GlcNAc. The enzyme formed the trisaccharides 13 in 13% overall yield based on the donor, and in the ratio of 40:37:23. In contrast, transglycosylation by Alcaligenes sp. α- -fucosidase led to the regioselective synthesis of trisaccharides containing a (1→3)-linked α- -fucosyl residue. When β- -Gal-(1→4)- -GlcNAc and lactose were acceptors, the enzyme formed regioselectively compound 2 and α- -Fuc-(1→3)-β- -Gal-(1→4)- -Glc (3′-O-α- -fucosyllactose, 4), respectively, in 54 and 34% yields, based on the donor.  相似文献   

19.
A radioimmunoassay (RIA) for the estimation of 6-keto-PGF 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-PGF was found to be lower than that reported for PGE2 or PGF. However, during the first week of life, significantly more 6-keto-PGF was excreted. The very high levels of 6-keto-PGF 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   

20.
Two potent non-steroidal inhibitors (CB7645 and CB7661) of human cytochrome P45017α were tested for in vivo activity in WHT mice. There were no signs of toxicity, but there was no effect on the androgen-dependent organs. The pharmacokinetics and biochemistry of the compounds in mice were investigated. Following i.p. administration of 0.5 mmol/kg of CB7645 and CB7661, peak plasma levels of 13.4 and 3.4 μM, respectively, occurred after 2–4 h, both compounds were cleared rapidly (terminal half-lives 2.7 and 3.3 h, respectively) and neither was detectable at 24 h. CB7645 produced some decrease in plasma testosterone at 4 h, but this was not sustained. When tested in vitro against the WHT testicular enzyme, the CB7645 and CB7661 were competitive inhibitors with Ki values of 10 and 13 nM, respectively. However, the Km for the substrate progesterone was lower at 4.3 nM. These data indicate that, for effective and continuous inhibition of the murine cytochrome P45017α enzyme, higher peak levels of the compounds would be required, and these levels would need to be maintained throughout the treatment period.  相似文献   

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