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1.
The synthesis of deuterium- and tritium-labeled analogs of 2,3-dinor-6-keto-prostaglandin F1α and of 6,15-diketo-13,14-dihydro-2,3-dinor-prostaglandin F1α is described. These analogs were used as internal standards in the assay of the corresponding unlabeled metabolites in human urine by stable isotope dilution and combined gas chromatography-mass spectrometry. In male subjects the 24-h urinary excretion of the two metabolites was found to be 719 ± 264 and 314 ± 115 ng, respectively. The method offers a noninvasive approach to the study of prostaglandin I2 synthesis in man. 相似文献
2.
The metabolism of endogenous PGI2 (released by angiotensin II or bradykinin) and exogenous PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase was studied in five different vascular beds of the anaesthetized cat. Plasma concentrations of 6-keto-PGF1α (the product of spontaneous hydrolysis of PGI2) and 6,15-diketo-13,14-dihydro-PGF1α (the metabolite formed from PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase) were determined in the efferent vessels of the respective vascular beds by specific radioimmunoassays.No major metabolism of PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase was detected in the head and the hindlimbs of the cat. In the lung exogenous (circulating) PGI2 was not metabolized, whereas PGI2 synthetized in the lung itself was converted to 6,15-diketo-13,14-dihydor-PGF1α. No significant amounts of 6,15-diketo-13,14-dihydro-PGF1α-immunoreactivity were detected in hepatic venous blood after infusion of PGI2 into the portal vein. However as also no 6-keto-PGF1α was found, the liver seems to efficiently extract PGI2 from the circulation. The cat kidney had the highest capacity of all vascular beds investigated to release endogenous and exogenous PGI2 as 6-15-diketo-13,14-dihydro-PGF1α. In other organs (vascular beds) investigated PGI2 is either metabolized less efficiently by the 15-hydroxy-PG-dehydrogenase or further transformed to other metabolites. 相似文献
3.
F.F. Sun B.M. Taylor F.H. Lincoln O.K. Sebek 《Prostaglandins & other lipid mediators》1980,20(4):729-733
The transformation of 6-keto-PGF1α to two prostacyclin metabolites, 2,3-dinor-6-keto-PGF1α (I) and 2,3-dinor-6,15-diketo-13,14-dihydro-PGF1α (II) by UC-6176 is described. The finding that the bacterium oxidized 6-keto-PGF1α to the 6,15-diketo metabolite II shows that it contains 15-hydroxy prostaglandin dehydrogenase and Δ13 reductase enzyme systems. 相似文献
4.
B. Sjöquist E. Oliw I. Lundén E. ÄnggÅrd 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1979,163(1):1-8
Analysis of prostaglandin F2α (PGF2α) in urine is a useful indicator of renal prostaglandin synthesis. A mass fragmentographic method for PGF2α analysis in human urine was developed using [3,3,4,4-2H4]PGF2α as an internal standard and carrier. PGF2α was extracted from urine (20 ml) with chloroform, purified by preparative thin-layer chromatography and converted to the methyl ester trimethylsilyl ether before analysis by gas chromatograph—mass spectrometry. The specificity of the urine analysis was demonstrated by retention time and the use of two pairs of fragments m/e 494/498 and 513/517 with the same results. The coefficient of variation for duplicate analysis averaged 12.6%, n = 17. Urine from recumbent women contained 4.9 ± 2.6 (S.D.) ng/ml or 4.1 ± 1.0 ng PGF2α per mg creatinine (n = 10) with little diurnal variation. Male urine contained 5.0 ± 2.7 (S.D.) ng/ml or 3.7 ± 2.1 ng/mg creatinine (n = 10). Similar concentrations were found in boys and in girls. These observations indicate that urinary PGF2α originates from the kidneys with little contribution from the male accessory sexual glands. This method can also be applied to analysis of PGF2α in rabbit urine. 相似文献
5.
The metabolism of endogenous PGI2 (released by angiotensin II or bradykinin) and exogenous PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase was studied in five different vascular beds of the anaesthetized cat. Plasma concentrations of 6-keto-PGF1α (the product of spontaneous hydrolysis of PGI2) and 6,15-diketo-13,14-dihydro-PGF1α (the metabolite formed from PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase) were determined in the efferent vessels of the respective vascular beds by specific radioimmunoassays.No major metabolism of PGI2 by 15-hydroxy-PG-dehydrogenase and Δ13-reductase was detected in the head and the hindlimbs of the cat. In the lung exogenous (circulating) PGI2 was not metabolized, whereas PGI2 synthetized in the lung itself was converted to 6,15-diketo-13,14-dihydor-PGF1α. No significant amounts of 6,15-diketo-13,14-dihydro-PGF1α-immunoreactivity were detected in hepatic venous blood after infusion of PGI2 into the portal vein. However as also no 6-keto-PGF1α was found, the liver seems to efficiently extract PGI2 from the circulation. The cat kidney had the highest capacity of all vascular beds investigated to release endogenous and exogenous PGI2 as 6-15-diketo-13,14-dihydro-PGF1α. In other organs (vascular beds) investigated PGI2 is either metabolized less efficiently by the 15-hydroxy-PG-dehydrogenase or further transformed to other metabolites. 相似文献
6.
To investigate the effects of acute ethanol administration on the production of proaggregatory thromboxane A2 (TxA2) and anti-aggregatory prostacyclin (PGI2), ethanol (1.5 g/kilogram body weight) was given to eight healthy nonsmoking men, and the stable metabolites thromboxane B2 (TxB2) and 6-keto-prostaglandin F1α (6-keto-PGF1α), respectively, measured by radioimmunoassay from serial blood samples before drinking and during the ensuing 18 hours. Each subject was studied as his own control on another occasion when only an equivalent volume of water was given. Serum TxB2 level decreased (p < 0.01) from 206 + 31 ng/ml (mean) ± S.E. to 1672 ± 24 and 161 ± 23 ng/ml (two and four hours after beginning of the drinking, respectively) concomitantly with the attainment of maximal blood ethanol concentrations (about 120 mg/100 ml), whereas no changes occurred in plasma 6-keto-PGF1α concentrations. Our results may provide an explanation for known effects of ethanol on platelet aggregation. They also raise speculation whether TxA2-inhibition and the antiatherogenic effect of alcohol intake are somehow related. 相似文献
7.
《Animal reproduction science》1995,40(3):193-201
The objective of this study was to determine if oxytocin-induced release of prostaglandin F2α (PGF2α; measured by the stable metabolite, 13,14-dihydro-15-keto-prostaglandin F2α (PGFM)) was inhibited following intrauterine infusion of bovine interferon-αI1 (rboIFNαI1) into postpartum cows anticipated to have short estrous cycles following first ovulation postpartum. Cows expected to have short estrous cycles were assigned to receive twice daily intrauterine infusions of either placebo (SCP; n = 11) or 2 mg rboIFNαI1 (SCIFN; n = 14) on Days 1–16 following hCG injection (2500 IU; day 0) on Days 30 or 31 postpartum. On Day 5 following hCG, each cow was injected with 100 IU oxytocin (i.v.) to induce the release of uterine PGF2α (as measured by PGFM). Other treatment groups consisted of cows expected to have normal estrous cycle lengths following pretreatment with a 9 day norgestomet implant on Days 21 or 22 postpartum followed by hCG injection to induce ovulation. Cows expected to have normal estrous cycle lengths received twice daily intrauterine infusions of either placebo from Days 1 to 16 of the cycle and 100 IU oxytocin (i.v.) on Day 5 (NCPE; n = 11) or twice daily infusions of placebo (NCPL; n = 7) or rboIFNαI1 (NCIFN; n = 10), from Day 13 post-hCG injection until luteolysis. Oxytocin was injected (100 IU; i.v.) into cows in the NCPL and NCIFN groups on Day 16. The calculated areas under the curve (arbitrary PGFM units) were: 164 ± 18 units, 96 ± 16 units, 93 ± 18 units, 137 ± 27 units and 53 ± 20 units for SCP, SCIFN, NCPE, NCPL and NCIFN, respectively (SCIFN < SCP; NCIFN < NCPL; P < 0.015). Mean luteal phase length was calculated as the number of days from injection of hCG until progesterone declined to below 0.5 ng ml−1 and was: 6.7 ± 1.0 days, 10.5 ± 0.9 days, 12.0 ± 1.0 days, 18.0 ± 1.3 days and 20.7 ± 1.1 days for SCP, SCIFN, NCPE, NCPL and NCIFN, respectively (SCP < SCIFN = NCPE < NCPL = NCIFN; P < 0.01). In summary, luteal phase lengths were increased and oxytocin-induced release of PGFM was reduced by rboIFNαI1 infusion in cows anticipated to have short luteal phases. 相似文献
8.
A radioimmunoassay has been developed for 13,14-dihydro-15-keto-prostaglandin F in bovine peripheral plasma. Acidified plasma samples were extracted with diethyl ether and the dried extracts assayed for 13,14-dihydro-15-keto-prostaglandin F using antiserum raised against a 13,14-dihydro-15-keto-prostaglandin F2α-albumin complex. The tracer used for the assay was prepared enzymatically from tritiated prostaglandin F1α. Polyethylene glycol was employed to separate free and bound 13,14-dihydro-15-keto-prostaglandin F. The inter-assay coefficient of variation based on 9 determinations of control plasma was 13.8%. The detection limit of the assay was 25 pg 13,14-dihydro-15-keto-prostaglandin F/ml plasma.In 3 cows around estrus there was a complex series of peaks of 13,14-dihydro-15-keto-prostaglandin F concentrations coincident with luteolysis and declining progesterone concentrations. Changes in peripheral plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F in the pregnant cow near term showed a close correlation with prostaglandin F levels in utero-ovarian venous plasma. The concentration of 13,14-dihydro-15-keto-prostaglandin F in 12 men was 114±20 pg/ml plasma. It is concluded that the measurement of peripheral 13,14-dihydro-15-keto-prostaglandin F concentrations may offer a simple and convenient method for monitoring uterine prostaglandin F production in the cow. 相似文献
9.
A radioimmunoassay has been developed for 13,14-dihydro-15-keto-prostaglandin F in bovine peripheral plasma. Acidified plasma samples were extracted with diethyl ether and the dried extracts assayed for 13,14-dihydro-15-keto-prostaglandin F using antiserum raised against a 13,14-dihydro-15-keto-prostaglandin F2α-albumin complex. The tracer used for the assay was prepared enzymatically from tritiated prostaglandin F1α. Polyethylene glycol was employed to separate free and bound 13,14-dihydro-15-keto-prostaglandin F. The inter-assay coefficient of variation based on 9 determinations of control plasma was 13.8%. The detection limit of the assay was 25 pg 13,14-dihydro-15-keto-prostaglandin F/ml plasma.In 3 cows around estrus there was a complex series of peaks of 13,14-dihydro-15-keto-prostaglandin F concentrations coincident with luteolysis and declining progesterone concentrations. Changes in peripheral plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F in the pregnant cow near term showed a close correlation with prostaglandin F levels in utero-ovarian venous plasma. The concentration of 13,14-dihydro-15-keto-prostaglandin F in 12 men was 114±20 pg/ml plasma. It is concluded that the measurement of peripheral 13,14-dihydro-15-keto-prostaglandin F concentrations may offer a simple and convenient method for monitoring uterine prostaglandin F production in the cow. 相似文献
10.
John G. Gerber Walter C. Hubbard Alan S. Nies 《Prostaglandins & other lipid mediators》1979,17(4):623-627
We studied the uterine venous plasma concentrations of prostaglandins E2, F2α, 15 keto 13,14 dihydro E2 and 15 keto 13,14 dihydro F2α in late pregnant dogs in order to evaluate the rates of production and metabolism of prostaglandin E2 and F2α in pregnancy . We used a very specific and sensitive gas chromatography-mass spectrometry assay to measure these prostaglandins. The uterine venous concentrations of prostaglandin E2 and 15 keto 13,14 dihydro E2 were 1.35±.27 ng/ml and 1.89±.37 ng/ml, respectively; however, we could not find any prostaglandin F2α and very little of its plasma metabolite in uterine venous plasma. Since uterine microsomes can generate prostaglandin F2α and E2 from endoperoxides, prostaglandin F2α production must be regulated through an enzymatic step after endoperoxide formation. Prostaglandin E2 is produced by pregnant canine uterus in quantities high enough to have a biological effect in late pregnancy; however, prostaglandin F2α does not appear to play a role at this stage of pregnancy. 相似文献
11.
J C Fr?lich 《Prostaglandins》1984,27(3):349-368
This statement from laboratories highly qualified in icosanoid analysis identifies the urgent need for the availability of the following compounds in labeled (deuterium and tritium) and unlabeled form: PGE2 PGF2 alpha PGD2 6-keto-PGF1 alpha Thromboxane B2 9 alpha,20-dihydroxy-11,15-dioxo-2,3- dinorprost -5-enoic acid 9 alpha-hydroxy-11,15-dioxo-2,3,18,19- tetranorprost -5-ene-1,20-dioic acid 15-keto-13,14-dihydro-PGE2 15-keto-13,14-dihydro-PGF2 alpha 5 alpha-7 alpha-dihydroxy-11- ketotetranorprosta -1,16-dioic acid 7 alpha-hydroxy-5,11-diketo- tetranorprosta -1,16-dioic acid 2,3 dinor-thromboxane B2 2,3 dinor-6-keto-PGF1 alpha 2,3 dinor-6,15-diketo 13,14 dihydro-20-carboxyl-PGF1 alpha 2,3 dinor-13,14-dihydro-6,15-diketo-PGF1 alpha LTB4 LTC4 LTD4 LTE4 LTF4 20-OH-LTB4 20-COOH-LTB4 5-HETE 12-HETE 15-HETE omega-OH-12-HETE 5S, 12S-di HETE 5S, 15S-di HETE HHT other hydroxylated polyunsaturated fatty acids and their epoxides. 相似文献
12.
U.-M. Mäkila E. Kokkonen L. Viinikka O. Ylikorkala 《Prostaglandins & other lipid mediators》1983,25(1):39-46
To study the synthesis of proaggregatory, vasoconstricting thrombone A2 (TxA2) by human fetal platelets we evaluated the formation of its stable metabolite thromboxane B2 (TxB2) during thrombin-induced spontaneous clotting of blood from the umbilical vein of 13 healthy infants. We further compared the effects of acetylsalicyclic acid, indomethacin, naproxen sodium and diclofenac sodium on platelet TxA2 production in response to thrombin-induced aggregation during spontaneous clotting, and on prostacyclic (PGI2) production by umbilical arteries in a superfusion system by measuring the 6-keto-prostaglandin F1α (6-keto-PGF1α) concentration in the superfusate. For every drug four concentrations covering the clinically significant range were studied. The basal production of TxB2 by fetal platelets (181.5±22.5 ng/ml, mean±SEM) was comparable with that of adults (216.1±11.5 ng/ml). The concentrations of the drugs needed for 50 % inhibition of TxB2 generation were 19.0 umol/1 for acetylsalicylic acid, 0.09 umol/1 for indomethacin, 0.06 umol/1 for diclofenac sodium and 4.2 umol/1 for naproxen sodium. The basal production of 6-keto-PGF1α by umbilical arteries was 24.5±3.2 ng/min/g. The concentrations of the drugs needed for 50 % inhibition of 6-keto-PGF1α production were 360.0 umol/1 for acetylsalicylic acid, 4.0 umol/1 for indomethacin, 2.3 umol/1 for diclofenac sodium and 15.0 umol/1 for naproxen sodium. Thus fetal platelet cyclo-oxygenase was 4–44 times more sensitive to these prostaglandin synthesis inhibitors than umbilical artery cyclo-oxygenase. 相似文献
13.
《Prostaglandins and medicine》1981,6(4):427-436
A radioimmunoassay for 6-keto-prostaglandin F1a (6-keto-PGF1α), a stable hydration product of prostacyclin (PGI2), is described. The method utilises plasma extraction with ethyl acetate and saturation analysis. Antiserum was produced in rabbits against 6-keto-PGF1α-BSA conjugate, and its cross-reactions with 22 prostaglandins and related compounds were insignificant. The mean mass of added 6-keto-PGF1α required to displace zero-point binding by 50 % was 55.6 ± 5.1 pg (mean ± SD, N = 10). The method blank was 7.8 ± 2.4 pg/ml (N = 10), resulting in a detection limit of 12.6 pg/ml (mean blank + 2 SD). The intro-assay variation was between 4.1 − 8.2 % at concentrations between 150.3 pg/ml and 560.7 pg/ml (N = 10). The interassay variation was 12.4 % (N = 15). The recoveries of 100 pg/ml or 200 pg/ml added to the plasma samples (N = 10) were 90.2% and 95.4 %, respectively. The 6-keto-PGF1a concentrations in healthy subjects ranged from 92.7 to 394.5 pg/ml with a mean of 182.5 pg/ml in plasma. The presence of acetylsalicylic acid or indomethacin in the collection tubes caused no changes in plasma 6-keto-PGF a concentration. Intravenous infusion of PGI2 (1–8 ng/kg/mini into 6 healthy women caused linear increases in 6-keto-PGF1α. concentrations in plasma. After the discontinuation of PGI2 infusion, the 6-keto-PGF levels decreased rapidly, the half-life being approximately 30 minutes. 相似文献
14.
《Animal reproduction science》1998,51(2):81-96
The effect of ICI 182,780, oestrogen antagonist, on the concentrations of oxytocin and uterine PGF2α was investigated in intact Border Leicester Merino cross ewes during the late oestrous cycle. Twelve cyclic ewes (n=6 per group) were randomly assigned to receive, at 6 h intervals, intra-muscular injection of either peanut oil or ICI 182,780 (1.5 mg kg−1 day−1) in oil for 2 days, starting at 1900 h on day 13 until 1300 h on day 15 post-oestrus. Hourly blood samples were collected via a jugular catheter from 0800 h on day 14 for 37 h and then daily over days 16, 17 and 18 post-oestrus. Peripheral plasma concentrations of oxytocin, the metabolite of prostaglandin F2α, 15-keto-13,14-dihydro-prostaglandin F2α, (PGFM) and progesterone were measured by radioimmunoassay. All ewes treated with ICI 182,780 exhibited functional luteal regression as indicated by a marked reduction in plasma progesterone concentrations to less than 1000 pg/ml over the period of 18–36 h during sampling period on days 14 and 15 of the oestrous cycle. In five of six vehicle-treated ewes, progesterone concentrations declined between day 16 and day 18 post-oestrus. In the remaining control ewe, progesterone concentrations reach less than 1000 pg/ml within 36 h of the commencement of the sampling period. During the frequent sampling period, the number of oxytocin pulses in the ICI 182,780 treated ewes was significantly higher compared to control ewes (2.7±0.3 vs. 0.8±0.3). The mean amplitude of oxytocin pulses observed was also greater (70.4±19.5 pg/ml) in ewes treated with ICI 182,780, but was not significantly different from control ewes (33.5±12.9 pg/ml). Oxytocin pulses may however have occurred following the initial two ICI 182,780 injections but before commencing blood sampling. The oxytocin pulses were detected at a mean of 3.2±0.2 h following each injection with ICI 182,780 during blood sampling. In the ICI 182,780-treated ewes, the pulsatile pattern of plasma PGFM in jugular blood samples over the 37 h sampling period on days 14 and 15 post-oestrus had a higher amplitude (512.9±158.9 vs. 121.7±78.7 pg/ml) and pulse area (618.1±183.3 vs. 151.5±102.9 (pg/ml)τ) compared to the vehicle-treated ewes (P<0.05) respectively. The average number of PGFM pulses observed per ewe was 3.0±0.7 in the ICI 182,780-treated group and was significantly (P<0.02) higher than the number of pulses (0.5±0.3) observed in ewes treated with vehicle alone. The PGFM pulses were detected at 4.2±0.6 h following each injection with ICI 182,780 during blood sampling. The percentage of PGFM pulses that occurred coincidently with a significant elevation of oxytocin concentrations was 44.4% in ICI 182,780-treated compared to 66.6% in control ewes. We conclude that administration of oestrogen antagonist ICI 182,780 accelerated development of the luteolytic mechanism by enhancing pulsatile secretion of oxytocin and PGFM which suggests that ICI 182,780 acts as an agonist for oxytocin and prostaglandin F2α release in intact ewes when administered at 1.5 mg/kg/day over Day 13 to 15 post-oestrus. 相似文献
15.
Lawrence Levine 《Prostaglandins & other lipid mediators》1977,14(6):1125-1139
A rabbit antiserum directed toward the prostaglandin E2 metabolite 13,14-dihydro-15-keto-prostaglandin E2 (KH2PGE2) was produced by immunization with a human albumin-KH2PGE2 conjugate. The antiserum recognized the 15-keto-group (it cross reacts with 13,14-dihydro-prostaglandin E2 0.2%); the saturated 13,14-bond (it cross reacts with 15-keto-prostaglandin E2 7%); the 9-keto group (it cross reacts with 13,14-dihydro-15-keto-prostaglandin F2α 5%); and the 11-hydroxy group (it cross reacts with 13,14-dihydro-15-keto-PGA2 0.4%).By subjecting the antiserum to preparative isoelectric electrofocusing, populations of antibodies that varied in their cross reaction with 13,14-dihydro-15-keto-prostaglandin F2α (KH2PGF2α) from 20% to 1% were obtained. The levels of KH2PGE2 in plasma of rat and mouse as measured by radioimmunoassay of the unfractionated plasma were 0.39 ± 0.07 ng/ml and 0.41 ± 0.13 ng/ml, respectively. Recovery of exogenously added KH2PGE2 from human plasma was 100%. Radioimmunoassay with two antisera; an antiserum directed toward KH2PGF2α that cross reacts with KH2PGE2 1% and the antiserum to KH2PGE2, demonstrated that KH2PGE2, not KH2PGF2α, was being measured with the anti-KH2PGE2. The levels of KH2PGE2 in rat plasma did not vary with sex. In rats, the levels of KH2PGE2 markedly increased after exercise stress.In mice carrying a spindle-cell sarcoma (SAI) and a fibrosarcoma (SaD2), the levels of KH2PGE2 in the plasma increased with time after transplantation. The increase was not observed in the plasma of mice carrying a transplantable anaplastic carcinoma (15091AK), a lymphatic leukemia (AW5147), two mammary adenocarcinomas (CADI, CAD2), a myeloid leukemia (C1498), and a hepatoma (BW7756). 相似文献
16.
Antibodies directed against prostaglandin F2α and its main circulating metabolite, 13,14-dihydro-15-keto-prostaglandin F2α, were insolubilized by reaction with ethylchloroformate. Suspensions of insolubilized antibodies retained immunogenic activity and were useful for the development of a simple and rapid solid phase radioimmunoassay for these two prostaglandins. Using this method, suppression of prostaglandin levels by the influence of indomethacin in vivo has been observed. Advantages of solid phase radioimmunoassay over current procedures are discussed. 相似文献
17.
Peripheral plasma concentrations of 13,14-dihdyro-15-keto-prostaglandin F2α (PGFM) and progesterone were determined during both luteolysis in the oestrous cycle and early pregnancy in four goats. Luteal regression, characterised by decreasing progesterone concentrations, began on day 12 or 13. PGFM concentrations showed a pulsatile pattern around this time, with peak concentrations increasingly markedly as progesterone levels fell and oestrus approached. During early pregnancy progesterone concentrations did not fall after day 12 and no marked elevation of PGFM above basal values of 50–150 pg/ml was detected. 相似文献
18.
Tapan K. Ghosh Amita Moitra Gopal K. Kunwar Jyoti S. D. Munshi 《Ichthyological Research》1986,33(3):280-285
Measurements of bimodal oxygen uptake have been made in a freshwater air-breathing fish,Notopterus chitala at 29.0±1(S.D.)°C. xhe mean oxygen uptake from continuously flowing water without any access to air, was found to be 3.58±0.37 (S.E.) ml O2 · h?1 and 56.84+4.29 (S.E.) ml O2 · kg?1 · h?1 for a fish weighing 66.92 + 11.27 (S.E.) g body weight. In still water with access to air, the mean oxygen uptake through the gills were recorded to be 2.49 ± 0.31 (S.E.) ml O2 · h?1 and 38.78 ± 1.92 (S.E.) ml O2 · kg?1 · h?1 and through the accessory respiratory organs (swim-bladder) 6.04±0.87 (S.E.) ml O2 · h?1 and 92.32±2.91 (S.E.) ml O2 · kg?1 · h?1 for a fish averaging 66.92±11.27 (S.E.) g. Out of the total oxygen uptake (131.10 ml O2 · kg?1 · h?1), about 70% was obtained through the aerial route and the remainder 30% through the gills. 相似文献
19.
P Y Wong J C McGiff F F Sun K U Malik 《Biochemical and biophysical research communications》1978,83(2):731-738
Metabolism of prostacyclin, [9-3H]PGI2, was examined in the isolated perfused rabbit lung and the post-microsomal supernate of rabbit lung homogenate. Two major metabolites of [9-3H]PGI2 from the lung perfusate were separated by thin-layer chromatography and radiometric gas-chromatography. These two products were identified as 6 keto-PGF1α and 6,15 diketo-13,14 dihydro PGF1α by mass-spectrometry; they represented 65% and 14% of the total radioactivity. When [9-3H]PGI2 was incubated with the lung homogenate in the presence of either NAD+ or NADP+, more than 36% and 25%, respectively, was converted to the 6,15 diketo-13,14 dihydro metabolite. 相似文献
20.
《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,691(1):131-138
Doxepin is a tricyclic antidepressant marketed as an irrational mixture of cis- and trans-geometric isomers in the ratio of 15:85. A convenient high-performance liquid chromatographic (HPLC) procedure for simultaneous quantitation of geometric isomers of doxepin and N-desmethyldoxepin in plasma and urine is described. The HPLC procedure employed a normal phase system with a silica column and a mobile phase consisting of hexane-methanol-nonylamine (95:5:0.3, v/v/v), a UV detector and nortriptyline as the internal standard. The liquid-liquid extraction solvent was a mixture of n-pentane-isopropanol (95:5, v/v). The limit of quantitation was 1 ng/ml for each isomer. The calibration curves were linear over the ranges 1–200 ng/ml (plasma) and 1–400 ng/ml (urine). In plasma, the accuracy (mean±S.D.) (97.53±1.67%) and precision (3.89±1.65%) data for trans-doxepin were similar to corresponding values for urine, i.e., 97.10±2.40 and 3.82±1.14%. Accuracy and precision data for trans-N-desmethyldoxepin in plasma were 97.57±2.06 and 4.38±3.24%, and in urine were 97.64±3.32 and 5.26±1.83%, respectively. Stability tests under three different conditions of storage indicated no evidence of degradation. The recovery of doxepin was 61–64% from plasma and 63–68% from urine. The method has been applied to analyses of plasma and urine samples from human volunteers and animals dosed with doxepin. 相似文献