共查询到20条相似文献,搜索用时 15 毫秒
1.
C.R. Pace-Asciak M.C. Carrara G. Rangaraj K.C. Nicolaou 《Prostaglandins & other lipid mediators》1978,15(6):1005-1012
Intact rings and homogenates of aorta from spontaneously hypertensive rats (SHR) contain enhanced capacity over normal rats (NR) to convert arachidonic acid into PGI2. The PGI2 synthetic system in SHR is stimulated to a greater extent than NR by norepinephrine. Indomethacin blocks this stimulation. PGE2 and PGF2α were detected in much smaller amounts in homogenates (undetected in rings) but their formation was not enhanced by the hypertensive tissue. The identity of PGI2 was based on 1) direct pharmacological assay on the rat blood pressure. In this system identical vasodepressor responses to PGI2 are observed after intracarotid and intrajugular administration 2) indirectly as 6-keto PGF1α isolated after incubation of aortic homogenates with tritiated arachidonic acid and 3) indirectly by GC-MS assay of PGE2, PGF2α and 6-keto PGF1α formed during incubation of aortic homogenates with excess unlabeled arachidonic acid. These results provide additional support to our recent hypothesis that PGI2, of aortic origin, might actively participate in the regulation of systemic blood pressure. Its enhanced formation by intact hypertensive vascular tissue reflects an increase in the number of enzyme molecules immediately available to the substrate. This could probably be an adaptive response to the elevated levels of catecholamines in the circulation. 相似文献
2.
Alicia Terragno Rachelle Rydzik Norberto A. Terragno 《Prostaglandins & other lipid mediators》1981,21(1):101-112
A fast and reliable method for the separation and quantitation of arachidonic acid metabolites PGF1α, PGF2α, PGD2, PGE1, PGE2, PGB2, PGA2, 6-keto PGE1, 6-keto PGF1α, T×B2 and 15-keto PGE2 by high-performance liquid chromatography has been developed. Utilizing a single reverse-phase column and a UV spectrophotometer, sensitivity as little as 30 nanograms of each of these prostaglandins can be separated and subsequently detected. Although this study was performed using standards, it is highly promising for future application to biological fluids. 相似文献
3.
John F. Gerkens John G. Gerber David G. Shand Robert A. Branch 《Prostaglandins & other lipid mediators》1978,16(5):815-823
Prostaglandins (PG)I2, PGE2 and 6-keto PGF1α were infused directly into the gastric arterial supply at 10−9, 10−8 and 10−7 g/kg/min during an intra-gastric artery pentagastrin infusion in anesthetized dogs. 6-keto PGF1α was also infused at 10−6 g/kg/min. Gastric arterial blood flow was measured continuously with a non-cannulating electromagnetic flow probe and gastric acid collected directly from the stomach. PGI2 and PGE2 produced similar dose-dependent increases in blood flow with an increase of more than four-fold at the highest dose. Both PGs inhibited acid output over this dose range with PGE2 having 10 times the potency of PGI2. 6-keto PGF1α was at least 1000 times less active than PGI2 or PGE2 at increasing blood flow and failed to inhibit acid output even at 10−6 g/kg/min. 相似文献
4.
Ryo Kawata Yoshihiro Urade Masayoshi Tachibana Osamu Mizukoshi 《Prostaglandins & other lipid mediators》1988,35(2)
The exogenous and endogenous syntheses of prostaglandins (PG's) by the cochlea of adult mongolian gerbils were studied
. After incubation of the whole membraneous cochlea with [3H]-arachidonic acid (AA), syntheses of PGF2α, 6-keto PGF1α, PGE2, thromboxane (TX) B2 and PGD2 were evidenced in this order. The synthesis of radioactive PG's was almost completely inhibited by incubation with 10−5 M indomethacin. No significant amounts of those PG's were detected by radioimmunoassay (RIA) in the cochlea obtained from animals killed by microwave irradiation at 5.0 kw for 0.8 sec. However, when the homogenate of the whole membraneous cochlea obtained from animals without microwave irradiation was incubated at 37°C for 0–15 min, PGD2, PGE2, PGF2α and 6-keto PGF1α were found to be formed from endogenous AA in the cochlea by RIA. PG's were formed already at 0 time to considerable level (PGD2, PGF2α and 6-keto PGF1α, 90–120 pg/cochlea; PGE2, 370 pg/cochlea), reached to the maximum level (PGD2, PGF2α and 6-keto PGF1α, 170–200 pg/cochlea; PGE2, 500 pg/cochlea) at a 5-min incubation, and then gradually decreased. On the other hand, the amount of TXB2 was lower than the detection limit by RIA (<50 pg/cochlea) even after the incubation. The cochlea was dissected into three parts: organ of Corti + modiolus (OC + M), lateral wall (LW), and cochlear nerve (CN), and then PG's formed by these tissues were determined after a 5-min incubation of the homogenates. In the CN and OC + M, PGE2 was the major PG (100 and 160 pg/tissue, respectively), and the amounts of PGD2, PGF2α and 6-keto PGF1α were about
of those of PGE2. In the LW, the amounts of PGD2, PGE2, PGF2α and 6-keto PGF1α were about the same level (70–100 pg/LW). 相似文献
5.
《Prostaglandins, Leukotrienes and Medicine》1986,21(1):15-22
While no significant effects on the in vitro production of PGF2α by homogenates of rat estrous uteri were observed in the presence of 10−3 and 10−6M Cu2+, the presence of Cu2+ at 10−4 and 10−5M was found to stimulate production with maximal synthesis of PGF2α occurring with 10−4M Cu2+. By contrast, the synthesis of PGE2 and PGI2 (determined as 6-keto PGF1α) were unaffected at all of the different Cu2+ concentrations used. When indomethacin and salicylic acid were tested for their effects on the Cu2+-mediated levels of PG synthesis by the homogenates, indomethacin (at 20μM) was found to cause similar pronounced decreases in PGF2α, PGE2 and 6-keto PGF1α whereas salicylic acid (400μM) showed preference towards suppressing PGE2 and 6-keto PGF1α production. 相似文献
6.
S.M. Casalino-Matsuda J.A. Linares A. Goldraij 《Prostaglandins, leukotrienes, and essential fatty acids》1997,56(6):457-460
The effects of restricted diet (50% of the normal intake during 25 days) on the metabolism of 14U arachidonic acid, were explored in uterine horn strips isolated from intact and ovariectomized rats, treated by 17 β-estradiol or controls. The metabolism of arachidonic acid into different eicosanoids, PGE2, PGF2α, 6-keto PGF1α and TXB2, showed that the restricted diet diminished PGE2 and PGF2α, in intact rats, significantly. In contrast, this kind of feeding did not produce any change in castrated rats.Tissue preparations from previously estrogenized intact and castrated normal-fed rats showed that the production of different metabolites decreased. A similar result was obtained in intact rats subjected to a restricted diet. Nevertheless, in castrated underfed rats, estrogens did not produce any effect on the various eicosanoids analysed.These results showed that in isolated uteri, the effects of 17 β-estradiol, on metabolite production from labelled arachidonic acid, are different from controls in ovariectomized diet-restricted rats. 相似文献
7.
Identification of prostaglandins and other arachidonic acid metabolites in experimental otitis media
《Prostaglandins, Leukotrienes and Medicine》1982,8(3):249-261
Although prostaglandins (PGs) have been detected in the middle ear fluids, the exact identification of PGs, and other arachidonic acid (AA) metabolites has not been made.The AA metabolites were identified in experimentally induced serous otitis media and purulent otitis media in chinchillas using a radiochromatography method. The relative abundance of each metabolite synthesized was also determined. Two major AA metabolites, 6-Keto-PGF1α and 15-hydroxy-5,8,11,13-eicosatetraenoic acid (15-HETE), were positively identified by gas chromatography-mass spectrometry.The AA metabolites in Eustachian tube obstructed middle ear mucosa (MEM) were predominantly 6-keto-PGF1α, followed by PGD2, 15-HETE, hydroxyheptadecatrienoic acid (HHT), PGF2α and PGE2. In infected MEM, the predominant product was 15-HETE followed by 6-keto-PGF1α, PGD2, HHT, PGF2α, and PGE2.The possible role of PGs and other AA metabolites in the pathogenesis of otitis media will be discussed. 相似文献
8.
J.A. Simon 《Prostaglandins & other lipid mediators》1978,15(3):383-397
A radioimmunoassay for 6-keto-prostaglandin F1α has been developed. The assay is accurate and sensitive but since the antiserum cross-reacts 5–10% with prostaglandins (PGs) of the E and F series, solvent extraction and thin layer chromatography are required fo absolute specifity. The assay has been validated by comparison with a radiochemical assay and by the use of an inhibitor of 6-keto PGF1α formation, 15-hydroperoxy arachidonic acid. 6-Keto PGF1α was found to have a low cross reaction with antisera directed against PGE2, PGF2α and thromboxane B2. 相似文献
9.
Satish K. Batta Gordon D. Niswender Benjamin G. Brackett 《Prostaglandins & other lipid mediators》1978,16(5):835-846
Experiments were carried out to assess the influence of prostaglandins (viz. PGE1, PGE2 and PGF2α) on plasma concentrations of FSH and LH in the female rhesus monkey. Monkeys were ovariectomized and treated with estradiol benzoate to suppress endogenous gonadotropin levels prior to these experiments. Femoral venous blood was taken at intervals following a single carotid arterial injection of the PG in anesthetized monkeys. FSH and LH concentrations, determined by radioimmunoassay, were not significantly altered in 4 control animals receiving saline (2) or ethanol-saline (2), the vehicles for PGF2α and for the E series PGs, respectively. PGE1 (5mg) effected dramatic elevations of LH within 5 min in 3 animals and the high plasma concentrations were maintained at least for 60 min. Similarly, 5.0 mg of PGE2 effected rapid elevation of LH concentrations, from 2- to 7-fold pre-injection levels in 3 animals. In contrast, FSH levels were not so markedly altered by PGE1 and PGE2, but in general, appeared to be somewhat decreased by these treatments. PGF2α had no effect on plasma FSH and LH concentrations. These data demonstrate the ability of PGs of the E series to elevate plasma LH concentrations in the rhesus monkey and support studies in other species suggesting a modulating role for PGs on gonadotropin secretion or release. 相似文献
10.
William E Hoffman Marc L Leavitt Ronald F Albrecht David J Miletich 《Prostaglandins & other lipid mediators》1981,21(6):899-904
Prostacyclin (PGI2), prostaglandin E2 (PGE2) and prostaglandin F2∝ (PGF2∝) were tested here in unanesthetized male Sprague-Dawley rats for their effects on the cardiovascular system as mediated by the Central nervous system. Cannulae were chronically implanted into the third cerebral ventricle, femoral arteries and femoral veins of rats. Both PGE2 and PGF2∝ induced increased arterial blood pressure and tachycardia by an action on the central nervous system. The changes seen with PGE2 were larger than those observed with PGF2∝. Only transient depressor effects were seen with PGI2 and these changes appeared to be due to the leakage of the substance into the peripheral vascular system. 相似文献
11.
In the past two decades there have been innumerable reports that prostaglandins (PGs) are essential for mammalian ovulation. However, we have recently found that a relatively low dose of 0.03 mg indomethacin (INDO) sc to PMSG/hCG-primed immature Wistar rats can significantly reduce ovarian PG levels without inhibiting the control ovulation rate of 60+ ova/rat (1–3). In view of this information, the present study was an effort to duplicate the earlier reports that PGs can reverse the “inhibitory” effect of INDO on ovulation. In control animals, which received PMSG and hCG only, the ovulation rate was 63.8 ± 4.5 ova/rat. This rate was reduced to 4.1 ± 1.1 ova/rat when the animals were injected with 1.0 mg INDO at 3 h after hCG. In no instance was this inhibition reversed when the animals were treated with 1.0 mg of PGE2 or PGF2α, or a combination of both prostanoids in either a single dose at 3 h after hCG, or in 4× doses at 2-h intervals beginning at 3 h after hCG. Furthermore, in animals that did not receive INDO, the ovulation rate in PGE2-treated animals was reduced to 20.0 ± 6.7 ova/rat, and in animals treated with PGE2 and PGF2α (combined) it was reduced to 19.4 ± 6.5 ova/rat. In summary, not only did the PGs fail to reverse the anti-ovulatory effect of INDO, PGE2 actually suppressed the ovulation rate. 相似文献
12.
The effect of prostaglandins F2∝, E1 and of 7-oxa-13-prostynoic acid on the newborn rat and rabbit ductus can be studied using the whole-body freezing technique. PGF2∝ and PGE1 were able to re-open the closing ductus arteriosus in adequately oxygenated animals. PGF2∝ administration was accompanied by a strong physical reaction in the rat but less in the rabbit. PGF1 had sedative effects in both animals. A prostaglandin antagonist, 7-oxa-13-prostynoic acid had no effect on normal ductal closure nor did it counteract the effects of PGF2∝ and PGE1. The role of prostaglandins in homeostasis during the fetal and newborn period may be to modify ductal tone. 相似文献
13.
Metabolism of prostaglandin E1 (PGE1) and F1α (PGF1α) was studied in the frog spinal cord, using a hemisected preparation in vitro and tissue homogenates (whole honiogenate and tissue fractions). In the intact tissue, PGE, was converted to three Metabolites, 1 to 111, whereas only Metabolites 11 and 111 werc detected in experiments with PGF1α. Work with tissue homogenatcs confirmed that PG transformation is enzymatic, and endproducts were identified as PGF1α (Metabolite 1), 15-kcto metabolite (Metabolite 11) and 15-keto-13,14-dihydro metabolite (Metabolite 111). The 15-keto-13,14-dihydro metabolite was formed via the 15-keto metabolite which is consistent with findings elsewhere. These results establish the presence in the frog spinal cord of two pathways for PG metabolism, consisting one of the 15-hydroxy prostaglandin dehydrogenase (15-PGDH) and the prostaglandin-A13- reductase (13-PGR), the other of the prostaglandin E 9-keto(α)-reductase (9K-PGR). 9K-PGR is regarded as an inactivating enzyme because amphibian spinal neurons are less responsive to PGF, than to PGE1. In the intact or in the homogenized tissue, PGE, is metabolized more efficiently by the 15-PGDH/13-PGR than by the 9K-PGR route. The 15-PGDH metabolizes PGE, more readily than PGF1α. The present findings, together with the previous demonstration of active PG synthesis in the tissue and the potent actions of exogenous PGs, strongly suggest that the PGs play an important role in the function of neurons in the frog spinal cord. 相似文献
14.
H. Thaler-Dao M. Ramonatxo M. Saintot J. Chaintreuil A.Crastes de Paulet 《Prostaglandins & other lipid mediators》1982,24(2):149-163
prostaglandin biosynthesis by uteri of ovariectomized rats and guinea pigs treated or untreated with oestradiol 17 β, administered subsutaneously, was measured by R.I.A. of PGF2α and PGE2. Incubations with [1-14C] arachidonic acid were also performed and labelled metabolites were analyzed by TLC. The main metabolite in rats was 6 keto PGF1α and in decreasing order of magniture, PGF2α and PGE2. In guinea pig PGF2ga was the main product. Ovariectomy in rats completely changed the pattern of synthesized prostanoids: PGI2 production was doubled when compared to cycling rats and PGE2 increased 10 fold. PGF2α walues were similar to the mean value measured during the cycle. OE2 treatment almost completely inhibited PGI2 synthesis and reduced PGE2 by half. Total PG synthesis in OE2 treated animals was decreased by 5 fold when compared to spayed rats. Endogenous PGFsα synthesis was slightly stimulated. In the guinea pig OE2 treatment of ovariectomized animals increased the total synthesis from 50 per cent. PGF2α was always the main metabolite. In conclusion OE2 regulation of uterine PG synthesis is depending on the animal species and cannot be explained by a unique effect on the cyclooxyhenase, but rather by an interplay on the various enzymes of the arachidonic acid cascade. 相似文献
15.
《Insect Biochemistry》1986,16(6):895-902
Prostaglandins (PGs) of the E and F series were quantified in the housefly by radioimmunoassay (RIA). Whole insects and reproductive tissues from both sexes contained PGE(1+2) and PDG2α which increased in amount with age. PGF2α levels were higher than PGE series in extracts of whole male and female insects and in ovaries. Male reproductive tissues contained higher amounts of PGE(1+2) than PGF2α. Gas chromatographic-mass spectrometric (GC-MS) analyses of the products formed after injection of arachidonic acid (20:4) and eicosatrienoic acid (20:3, n-6) into male and femal insects demonstrated the conversion of 20:4 to PGF2α and 20:3 to PGF1α. Radiolabeled 20:4 injected into houseflies was rapidly converted to PGE2 and PGF2α. The catabolism of PGE2 was more rapid than PGF2α in males, whereas in females, PGE2 and PGF2α were converted to more polar products at similar rates. Radiolabeled 20:4 injected in the hemolymph was incorporated into the reproductive tracts of male insects. About 2.1% of the total radioactivity from [3H]20:4 injected into males just prior to mating was transferred to females during mating. Thus, PG are formed from 20:4 in male and female houseflies. During mating, 20:4 is transferred from males to females where it can be metabolized to PGF2α. 相似文献
16.
《Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism》1996,1299(2):267-277
Endothelial cells release several factors which influence vascular tone, leukocyte function and platelet aggregation. Some of these factors are metabolites of arachidonic acid, most notably prostacyclin. However, many of the endothelial metabolites of arachidonic acid have not been positively identified. The purpose of these studies is to identify the arachidonic acid metabolites synthesized by bovine coronary endothelial cells. Cultured bovine coronary artery endothelial cells were incubated with [ 14C]arachidonic acid. The incubation media was extracted and the radioactive metabolites resolved by a combination of reverse phase- and normal phase-high pressure liquid chromatography (HPLC). The cells synthesized 6-keto prostaglandin (PG)F1α, PGE2, 12-hydroxyheptadecatrienoic acid (HHT), 12-, 15-, and 11- hydroxyeicosatetraenoic acids (HETE), and 14,15-, 11,12-, 8,9-, and 5,6-epoxyeicosatrienoic acids (EET). Several of the HETEs were further analyzed by chiral-phase HPLC. The cells synthesized predominately 12(S)-, 15(S)-, and 11(R)-HETE. The synthesis of the S optical isomers of 12- and 15-HETE suggested that the 12- and 15-lipoxygenases were present in these cells. 11(R)-HETE is probably derived from cyclooxygenase. They also synthesized smaller amounts of 9-, 8- and 5-HETEs. The structures of the HETEs and EETs were confirmed by mass spectrometry. The release of 6-keto PGF1α and 15-HETE was measured by specific radioimmunoassays. Melittin, thrombin, arachidonic acid and A23187 stimulated the release of both eicosanoids in a concentration-related matter. Under all conditions, the release of 6-keto PGF1α exceed the release of 15-HETE. Therefore, cultured bovine coronary artery endothelial cells synthesize cyclooxygenase, lipoxygenase and cytochrome P-450 metabolites of arachidonic acid. 相似文献
17.
We have tested the action of a catechol oestrogen -2,3,17β- trihydroxy oestra-1,3,5 (10)-triene (2-OH oestradiol) in stimulating prostaglandin (PG) production by an homogenate of rat uterus. Marked and dose dependent stimulation was observed in PGF2α and PGE2 production using 20–250 μM concentrations of catechol oestrogen; a concentration of 250 μM 2-OH oestradiol resulted in a 23 fold increase in PGF2α production with a 50% reduction in the synthesis of 6-keto PGF1α. Tryptophan, catechol and glutathione were without effect on PGF2α and PGE2 production whereas adrenalin stimulated the production of all PGs, although the increase was less than that seen with 2-OH oestradiol. Oestradiol had a slight stimulatory action on PGF2α production which reached a maximum at around 40 μM but had a more marked stimulation of 6-keto PGF1α formation. Stimulation of prostaglandin production by oestradiol and 2-OH oestradiol showed no variation at different stages of the rat oestrous cycle. The use of 5 to 100 mg of tissue/ml gave similar product distribution although the effect of catechol oestrogen both in terms of stimulation of E and F formation (expressed per mg of tissue) and in its action on product distribution was more marked at lower concentrations of tissue. 相似文献
18.
Prepubertal gilts given 750 IU pregnant mares′ serum gonadotropin (PMSG) followed 72 h later by 500 IU human chorionic gonadotropin (hCG) to induce follicular growth and ovulation fail to ovulate when 10 mg/kg indomethacin (INDO) is injected 24 h after hCG administration. This study examines the effects of administration of exogenous prostaglandins F2α and E2 (PGF2α and PGE2) alone or in combination, and at various times prior to the expected time of ovulation, on the INDO blockade of ovulation in PMSG/hCG-treated gilts. Occurrence of ovulation was determined by visual observation at laparotomy 48 h after hCG. When 5 mg or 10 mg PGF2α was injected at each of 38, 40 and 42 h after hCG injection, 63% and 79%, respectively, of preovulatory follicles ovulated. In contrast, injection of 5 mg PGE2 or 5 mg PGE2 plus 5 mg PGF2α induced ovulation in 0% and 24% of preovulatory follicles, respectively. In control groups, 100% of folicles in PMSG/hCG-treated gilts ovulated whereas none did so in PMSG/hCG/INDO-treated animals. These results indicate that administration of PGF2α can induce ovulation in the PMSG/hCG/INDO-treated prepubertal gilt and suggest that PGE2 is ineffective and may be antagonistic to PGF2α in overcoming the ovulation blocking effect of INDO. 相似文献
19.
H. Thaler-Dao M. Saintot M. Ramonatxo C. Chavis A.Crastes de Paulet 《Prostaglandins & other lipid mediators》1982,23(3):347-359
Prostaglandin biosynthesis was studied in the rat uterus during the oestrous cycle. Uterine homogenates were incubated for 20 minutes in the presence of exogenous substrate (2.10−5M). PGF2α and PGE2 were measured by R.I.A.. A sharp peak PGF2α and a smaller peak of PGE2 were observed at prooestrus, 20 h. Another small PGE2 peak occurred at dioestrus II, 15 h. The lowest values of both PGs were found on dioestrus, 15 h. Plasma oestradiol concentration were highest at proestrus, 15 h and 20 h. A sharp progesterone peak occurred at prooestrus, 20 h. The PGF2α peak is next to the oestradiol peak and is superimposable or lags slightly beyond the progesterone peak.Incubation with 14C arachidonic acid and subsequent analysis of extracts by TLC and scanning showed that the major metabolite is PGI2, identified as 6 keto PGF1α. The conversion rate of arachidonic acid into 6 keto PGF1α is 5 times higher than into PGF2α. 6 keto PGF1α was further identified by GC/MS. No significant difference was observed between 6 keto PGF1α production during oestrus and dioestrus. 相似文献
20.
J.F. Burka M. Ali J.W.D. McDonald N.A.M. Paterson 《Prostaglandins & other lipid mediators》1981,22(5):683-691
Specific radioimmunoassays were used to demonstrate the synthesis by the guinea pig trachea of 6-keto PGF1α, TxB2, and PGF2α in addition to PGE2. The rank order of both spontaneous and stimulated release was PGE2 > PGF2α > 6-keto PGF1α = TxB2. Ovalbumin-induced prostanoid release from sensitized tissue was antigen-specific. The release was unlikely to be a secondary consequence of tracheal contraction since incubations with calcium ionophore A23187, at a concentration which produces an equivalent magnitude of contraction of sensitized trachea, did not induce a significant PG or Tx production. In contrast, significantly higher prostanoid synthesis was induced by A23187 in unsensitized than sensitized trachea. Thus sensitization altered the profile of arachidonic acid metabolism evoked by the ionophore. 相似文献