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1.
Prostaglandin synthesis in rat embryo tissue: The effect of non-steroidal anti-inflammatory drug and
Kenneth L. Klein Kenneth E. Clark William J. Scott 《Prostaglandins & other lipid mediators》1984,27(5):659-672
Aspirin and salicylate are well-known but poorly understood teratogens in laboratory animals. Because aspirin inhibits PG synthesis, we systematically examined PG synthesis in rat embryo homogenates, the inhibition of PG synthesis and by various non-steroidal anti-inflammatory drugs, and tested the hypothesis that the inhibition of PG synthesis is responsible for aspirin-induced limb defects in rats. We report that embryonic rat homogenates synthesis 6-keto-PGF1α, PGE, and PGF in large amounts from endogenous substrate, that aspirin and other non-steroidal anti-inflammatory drugs inhibit PG synthesis but not necessarily , and that contrary to our original hypothesis, the inhibition of PG synthesis is likely not responsible for aspirin-induced limb defects in rats. 相似文献
2.
OKY-1581 is an effective inhibitor of thromboxane synthesis and . The generation of thromboxane B2 (TxB2), prostaglandin E (PGE) and prostaglandin F (PGF) was measured following clotting and during platelet aggregation induced by collagen. The presence of OKY 1581 either or caused a reduction in TxB2 generation during clotting and platelet aggregation with a concomitant increase in PGE and PGF. The effect could be observed two hours after oral or subcutaneous administration of 5 to 100 mg per rabbit and lasted for 24 to 48 hours. The reduction in TxB2 was not accompanied by an inhibition of clotting or platelet aggregation. OKY-1581 appears to be a suitable agent for studying the role of TxB2 in atherosclerosis. 相似文献
3.
Norman A. Nelson R.W. Jackson A.T. Au D.J. Wynalda E.E. Nishizawa 《Prostaglandins & other lipid mediators》1975,10(5):795-806
The synthesis of -4,5,6-trinor-3,7-inter--phenylene-3-oxaprostaglandins oxaprostaglandins of the E1 and F1α series7 from 6-endo-(1-heptenyl)-bicyclo[3:1:0]hexan-3-one (III), is described. Preliminary biological screening data for gerbil colon smooth muscle stimulation, rat blood pressure and substrate specificity toward 15-hydroxyprostaglandin dehydrogenase is presented. Platelet function studies, both and of -4,5,6-trinor-3,7-inter--phenylene-3-oxa-PGE1, methyl ester (VIII) are presented. 相似文献
4.
John W. Wilks Kristi K. Forbes Jerome F. Norland 《Prostaglandins & other lipid mediators》1973,3(4):427-437
Prostaglandin F2α (PGF2α) did not alter the biosynthesis of progesterone by slices of luteinized rat ovaries when used in concentrations from 1 to 10,000 ng/ml of incubation medium; likewise, PGF2α did not affect the incorporation of acetate-1-14C into progestins. PGF1α, 15-keto PGF2α, and PGE1 did not alter the biosynthesis of progesterone by luteinized rat ovaries; PGE2 inhibited the production of progesterone when used at a concentration of 10 μg/ml, but not at lower doses. PGF2α in combination with luteinizing hormone (LH) enhanced the metabolism of progesterone to 20α-hydroxypregn-4-en-3-one in luteinized rat ovaries. Interestingly, PGF2α, at a high concentration of 10 μg/ml, did stimulate progesterone biosynthesis by slices of ovarian tissue from immature rats hormonally primed to simulate “pseudopregnancy,” suggesting a steroidogenic action of prostaglandins on the ovarian follicular or interstitial cell. PGF2α (10 μg/ml) did not stimulate the biosynthesis of progesterone or 20α-hydroxypregn-4-en-3-one by slices of rabbit corpora lutea or rabbit ovarian interstitial tissue. It is concluded that prostaglandins do not stimulate progestin biosynthesis in rat luteal tissue. 相似文献
5.
Bovine articular chondrocytes, cultured as cell suspensions and monolayers, produced prostaglandin (PG) E2 and PGI2 (assayed as 6 keto PGF1α), rather less PGF2α and irregular quantities of thromboxane (Tx) B2. Addition of foetal calf serum to the medium greatly stimulated PG production (a sixfold increase in PGE2 and a twofold increase in 6 keto PGF1α).Prostanoid production by cell suspension grown in serum-free medium generally plateaued after 24 hours. In the presence of 20% foetal calf serum, prostanoid production in long-term monolayer cultures increased during the first 6 days of culture. Levels of PGE2α levels remained high. Indomethacin (10-6M) inhibited chondrocyte PG production both in the presence and absence of added arachidonic acid (10-4M). Prostanoids produced by chondrocytes may play a role in the modulation of cartilage metabolism . 相似文献
6.
George M. Stancel Judy S. Ireland Venkat R. Mukku Alice K. Robison 《Life sciences》1980,27(12):1111-1117
The pesticide o,p'-DDT stimulates the production of a specific uterine protein, the so-called induced protein or IP, normally associated with an estrogenic response of the uterus. stimulation of IP production is observed 1 hour after the administration of 250 mg/kg of o,p'-DDT to immature rats. stimulation of IP production is observed after a 1 hour incubation of uteri with 100 μM o,p'-DDT. This response is blocked by Actinomycin D. In contrast to o,p'-DDT, which binds to the cytoplasmic estrogen receptor and stimulates IP production, p,p'-DDT which does not bind well to the estrogen receptor does not stimulate IP production . These findings represent the first report of an estrogenic effect of o,p'-DDT in a completely system. 相似文献
7.
The ability of various prostaglandins (PGs) to affect the anamnestic immune response of keyhole limpet hemocyanin (KLH)-primed rabbit popliteal lymph node cells was investigated. Of the four PGs studied (PGA1, PGE2 and PGF2α), PGE1 was found to have a stimulatory effect, whereas PGA1, PGE2 and PGF2α were ineffective in stimulating or inhibiting the anamnestic response. Under the conditions studied, a 3.5-fold increase in antibody production was obtained in PGE1-treated, KLH-stimulated cultures. Maximum enhancement was obtained when 0.2 μg of PGE1 were added at the time of culture initiation and were allowed to remain in contact with the lymph node cells for 24 hours. 相似文献
8.
Uterine stage embryos collected from the hamster (8-cell) and cow (morula, early blastocyst) were monitored for development (embryo culture) and (embryo transfer) following premature removal of the zona pellucida.Removal of the zona pellucida did not significantly affect development to the blastocyst stage of (1) 8-cell hamster embryos (zonae removed by a combined enzymic-mechanical procedure), (2) bovine morulae (zonae removed by mechanical means only) (3) early bovine blastocysts (zonae removed by the enzymic-mechanical technique).Zona-free hamster embryos formed significantly fewer viable fetuses than did zona-intact embryos. The lower incidence of fetal development observed following transfer of zona-free 8-cell hamster embryos may have resulted in part from the formation of chimeras by fusion of these embryos . Such fusion was observed to occur between zona-free embryos placed in close proximity. The proportion of pregnancies resulting from transfer of bovine blastocysts cultured from zona-free morulae was similar to that of zona-intact embryos.In this study we have demonstrated that (1) enzymic and mechanical procedures used to remove zonae pellucidae from uterine-stage hamster and bovine embryos do not adversely affect subsequent development of these embryos and and (2) zonae pellucidae are not required for normal development of these embryos. These findings have implications for microsurgery of mammalian embryos and for embryo transfer. 相似文献
9.
Daniel H. Riddick Anthony A. Luciano William F. Kusmik Ila A. Maslar 《Life sciences》1978,23(19):1913-1921
Relatively large amounts of immunoreactive prolactin were measured in homogenates of human decidual tissue obtained immediately after delivery of normal term pregnancies. In order to study the release and possible synthesis of prolactin by this tissue, explants of decidua were incubated for 24 hours at 37°C in oxygenated Gey's buffer containing 20% fetal calf serum. When cycloheximide was added to the medium in concentrations sufficient to prevent protein synthesis, 85–90% of the prolactin present in the tissue was released into the medium during the first 3 hours of incubation. No additional prolactin accumulated in either the medium or the tissue during the remainder of the incubation period. In the absence of cycloheximide, the prolactin concentration in the medium increased progressively during incubation, so that after 24 hours the total amount of hormone present in the tissue and medium was significantly greater than that in the tissue and medium prior to incubation (37.6 ± 9.6 ng/ml at 0 time vs 82.2 ± 7.7 ng/ml at 24 hours). When 3H-1-leucine (100 u Ci) was supplied during incubation, radioactive proteins were detected in the medium at 24 hr, 14–20% of which were specifically precipitated by antiserum to human pituitary prolactin. When aliquots of this medium were chromatographed on Sephadex G-100, 80–95% of the 3H-proteins precipitated by antiserum to pituitary prolactin eluted in the same position as did purified, iodinated pituitary prolactin. These data indicate that a species of prolactin which is identical to pituitary prolactin by the criteria of immunoprecipitation and gel chromatography is synthesized by human decidual tissue . 相似文献
10.
Guanylate cyclase from crude homogenates of vegetative has been characterized. It has a pH optimum of 8.0, temperature optimum of 25°C and requires 1 mM dithiothreitol for optimal activity. It strongly prefers Mn++ to Mg++ as divalent cation, requires Mn++ in excess of GTP for detectable activity, and is inhibited by high Mn++ concentrations. It has an apparent Km for GTP of approximately 517 μM at 1 mM excess Mn++.The specific activity of guanylate cyclase in vegetative homogenates is 50–80 pmoles cGMP formed/min/mg protein. Most of the vegetative activity is found in the supernatant of a 100,000 x g spin (S100). The enzyme is relatively unstable. It loses 40% of its activity after 3 hours storage on ice. Enzyme activity was measured from cells that had been shaken in phosphate buffer for various times. It was found that the specific activity changed little for at least 8 hours. Cyclic AMP at 10?4 M did not affect the guanylate cyclase activity from crude homogenates of vegetative or 6 hour phosphate-shaken cells. 相似文献
11.
The synthesis and characterization of - and -3,4-bis(4-hydroxyphenyl)-2-hexene (- and -pseudo-DES) and of -3,4-bis(4-hydroxyphenyl)-2-hexen-1-ol (-1-hydroxypseudo-DES) are described. These compounds are useful as probes in the study of hormone action. 相似文献
12.
Leonard A. Koltun Joseph LoBue Torgny N. Fredrickson Albert S. Gordon 《Life sciences》1976,19(12):1907-1912
The semi-soft agar colony assay permits an analysis of committed myeloid stem cell (CFU-c) proliferation capacities. In this paper this procedure has been used in combination with prior diffusion chamber culturing to determine the effect of host influences upon this committed stem cell population. This “double-seeding” procedure of first culturing bone marrow cells in diffusion chambers and then re-seeding them in agar furnishes data suggesting a relationship between diffusion chamber transitional lymphocytes and CFU-c seeding capacities. Diffusion chamber culturing offers a means of monitoring granulopoiesis and selects for enrichment of stem cell numbers. Detection and quantification of diffusion chamber stem cell enrichment is easily assessed by seeding chamber contents into the agar colony assay. 相似文献
13.
Metabolism of radiolabeled arachidonic acid (1AA) by blastocysts and endometrial slices recovered from five gilts 16 days after detection of estrus was studies . Blastocysts from each gilt were divided into four 216 ± 18 mg, and each portion was placed into a separate petri dish containing 15 ml modified minimum essential medium (MEM)_. The incubates from each gilt received either 25, 50, 100 or 200 μg radioinert arachidonic acid (AA). Endometrium was dissected from each uterin horn, sliced and duplicate 509 ± 3 mg portions from each gilt were placed into petri dishes containing 15 ml MEM and 200 μm AA. All incubates received 5 νCi of 1AA (either [14C]-arichidonic acid or [3H]-arichidonic acid). The incubates were rocked at 37°C for 24 h in an atmosphere of 50% n2:45% O2:5% CO2. After incubation, tissues and MEM were separated by centrifugation. Metabolism of 1AA was assessed in extracts of MEM and tissue homogenates by separating 1AA and its metabolites on columns of Sephades LH-20. Blastocysts produced compounds that migrated with [3H]-13,14-dihydro-15-keto-PGF2α (1PGFM), [3H]-PGE2 (1PGE2) and [3H]-PGF2α (1PGF2α). The greatest (P<.05) proportion (35.7 ± 1.8%) of the radioactivity in blastocyst MEM was recovered as PGE2. In blastocyst homogenates, most (66.2 ± 3.3%; P<0.05) of the radioactivity was in a nonporal peak assumed to be arachidonate esters. The concentration of AA ni MEM did not alter metabolism of 1AA by blastocysts. Endometrial slices produced 1PGFM and 1PGE2 but only in small amounts, and they were capable of producing nonpolar, probably esterified, forms of 1AA. It was concluded that porcine blastocysts produced and metabolized prostaglandins and that they make a contribution to the uterine milieu during early pregnancy. 相似文献
14.
David A. Ellwood Murray D. Mitchell Anne B.M. Anderson A.C. Turnbull 《Prostaglandins & other lipid mediators》1980,19(3):479-488
A method of tissue superfusion has been used to measure prostanoid production by the ovine cervix during late pregnancy and at parturition. In late pregnancy (105–135 days of gestation) cervical tissue produced relatively large amounts of prostaglandin E (PGE); in comparison, the production rates of prostaglandin F (PGF), 13, 14-dihydro-15-oxo-prostaglandin F (PGFM) and 6-oxo-prostaglandin F1α were generally low. Thromboxane B2 (TXB2) production was minimal and often unmeasurable. There were significant increases in the production rates of PGE and 6-oxo-PGF1α by cervical tissue taken immediately after delivery, when compared to late pregnancy. Mean production rates of PGE increased from 19.8 ± 4.1 to 43.8 ± 7.4 ng/g. dry wt./min; 6-oxo-PGF1α production rates increased more than three-fold from 10.0 ± 2.7 to 34.6 ± 9.8 ng/g. dry wt./min (means ± S.E.M.). There were no significant differences in the rates of production of PGF, PGFM and TXB2 by the two groups. 相似文献
15.
Edward W. Voss James E. Babb Peyton Metzel Jeffrey L. Winkelhake 《Biochemical and biophysical research communications》1973,50(3):950-956
Rabbit anti-fluorescyl antibody producing lymphoid cells incubated with LSD do not secrete the 7S form of immunoglobulin. The low molecular weight extracellular labeled material shows no measurable anti-fluorescyl antibody activity. Results indicate that during a short incubation period LSD interferes with tryptophan incorporation into antibody protein. 相似文献
16.
R.M. Sharpe D.G. Doogan I. Cooper 《Biochemical and biophysical research communications》1982,106(4):1210-1217
Injection of a luteinizing hormone-releasing hormone (LHRH) agonist into 55-day-old male rats which had been hypophysectomized 3 days earlier resulted in a 10- to 30-fold increase in the levels of testosterone in serum and testicular interstitial fluid (IF) in the 4h following injection. The levels achieved were within or above the normal range for intact untreated rats of this age. In similar animals, injection of LHRH agonist also enhanced the serum testosterone response to injected hCG at , but not at later times after injection, and by 24h reduced IF levels of testosterone suggested that LHRH agonist had begun to inhibit stimulation by hCG. , dispersed Leydig cells from untreated hypophysectomized rats showed a 2-fold increase in testosterone responsiveness to LHRH agonist when compared to cells from intact rats, and this change was associated with an 80% increase in the number of Leydig cell LHRH-receptors. 相似文献
17.
Tomasz Twardowski Janet M. Hill Herbert Weissbach 《Biochemical and biophysical research communications》1976,71(3):826-833
Extracts of 40 hr nauplii can convert a heavy form of elongation factor 1 (EF-1H) to a light species (EF-1L). The data indicate that a protease in the extracts is responsible for this reaction, and these findings may explain the observation that extracts from nauplii have only EF-1L whereas before hatching of the embryos EF-1H is the predominant species (Slobin and M?ller [1975] Nature 258, 452–454). 相似文献
18.
W.A. Chamley M.M Bagoyo G.D. Bryant-Greenwood 《Prostaglandins & other lipid mediators》1977,14(4):763-769
Paired segments of rat uterus were treated with relaxin (W1164-3, 150 GPU/mg) until the amplitude of contraction was reduced to at least 50% of the pre-treatment amplitude. Test segments then received 100 ng of either PGE1, PGE2, PGF2α or 250 uU of oxytocin. Control segments remained untreated. There was a significant increase in contraction amplitude in response to the spasmogens (P < 0.05) but no increase was seen in controls. 相似文献
19.
Robert D. Koos Martin R. Clark Per O. Janson Kurt E.B. Ahrén William J. LeMaire 《Prostaglandins & other lipid mediators》1983,25(5):715-724
Prostaglandin (PG) levels in follicular fluid from preovulatory follicles of rabbit ovaries perfused were measured in order to compare PG changes in this model system with those that occur and in isolated, LH-treated follicles . One ovary from each rabbit was perfused without further treatment (control). The other ovary was exposed to LH (0.1 or 1 ug/ml) beginning 1 hour (h) after initiation of perfusion. Samples of perfusion medium were taken at frequent intervals for measurement of PGE, PGF, progesterone and estradiol 17β. The perfusions were terminated when the first ovulation occurred or appeared imminent as judged by changes in the size and shape of the follicles. Follicular fluid was then rapidly aspirated from all large follicles on both ovaries for PGE and PGF measurement.Ovulations occurred only in the LH-treated ovaries. Progesterone and estradiol levels were significantly elevated in the perfusion medium within 1 h of LH treatment in comparison to controls. PG levels in perfusion medium from the control and LH-treated ovaries were not different throughout perfusion and increased in both groups. In contrast, PG levels measured in follicular fluid from LH-treated ovaries were 4- to 5-fold greater than in fluid from control ovaries. It is concluded that ovulation induced by LH in this experimental model is accompanied by an increase in follicular PG levels similar to that seen in other and models. This difference in follicular PG levels between the LH-treated and control ovaries is, however, not reflected in the perfusion medium. 相似文献
20.
Both pairs of -ll-desoxy- and -13---15, 16-dihydroxyprostaglandins have been synthesized via 1,4-conjugate additions of an appropriately functionalized -vinyl cuprate to the requisite cyclopentenone. These prostaglandin analogs are considerably less potent than PGE2 as gastric secretion inhibitors or as bronchodilators. 相似文献