共查询到20条相似文献,搜索用时 25 毫秒
1.
T J Gilbertson M J Ruwart R P Stryd M N Brunden N M Friedle B D Rush C A Christianson 《Prostaglandins》1983,26(5):745-759
Oral and subcutaneous administration of 16,16-dimethylprostaglandin E2 (16,16-dimethyl PGE2) resulted in an increase in the dry weight of the stomach and small intestine of the female rat. This weight response was rapid, controlled rather than continuously progressing, dose dependent and reversible. The dry weight of the colon also increased but this was not studied in detail. Two-day treatment with 16,16-dimethyl PGE2 caused an increase in the incorporation of 3H-thymidine into the duodenum, jejunum and colon suggesting an increase in cell number. Incorporation into the stomach and ileum was not changed. The number of goblet cells per crypt was increased by prostaglandin treatment in all parts of the small intestine. Since these are mucus producing cells, the small intestine may have increased in cell number and mucus production. Both anti-secretory and cytoprotective doses of 16,16-dimethyl PGE2 caused weight increases in the stomach and small intestine. However, the weight gain by itself was not sufficient to protect the stomach or small intestine from necrotic agents after the prostaglandin was discontinued. 相似文献
2.
T.J. Gilbertson R.P. Stryd M.N. Brunden C.A. Christianson B.D. Rush 《Prostaglandins & other lipid mediators》1984,27(6):887-898
Thymidine uptake in the organs of the gastrointestinal tract of the rat was studied to determine if cell synthesis was involved in the increases in weight of the stomach, small intestine and colon which result from treatment with 16,16-dimethyl prostaglandin E2 (16,16-dimethyl PGE2). Animals were treated for 2 days with 16,16-dimethyl PGE2. They were injected with the 3H-thymidine, sacrificed and the organs of interest were removed. The total amount of tritium in the stomach, duodenum, jejunum, ileum, and colon was determined.Thymidine uptake was significantly increased in the duodenum (1.50 times), jejunum (1.53 times), and colon (1.40 times) but not in the stomach and ileum. The increases were dose related in the duodenum and jejunum. The colon showed a similar dose response pattern but the changes with dose did not reach significance.These results confirm and extend a previous report that 16,16-dimethyl PGE2 increased thymidine uptake in the duodenum but not the stomach (1). This is different from gastrin which has been shown by others to increase thymidine uptake in the stomach, duodenum, ileum and colon (2,3). 相似文献
3.
Ruggero Fariello Peter M. Olley Flavio Coceani 《Prostaglandins & other lipid mediators》1977,13(5):901-907
Six newborns with obstructive right heart lesions were examined neurologically and electroencephalographically during treatment with prostaglandin (PG) E1 or E2 given to maintain patency of the ductus arteriosus and to increase pulmonary blood flow. PG was administered intravenously or intraarterially in the aortic isthmus proximal to the ductus arteriosus. Besides a rise in arterial oxygen saturation, all patients had some sign of central nervous system involvement. The electroencephalogram showed minor changes suggestive of sedation. In addition, three patients in whom PG given intravenously presented various combinations of neurological abnormalities (“myoclonic jerks”, apnoeic spells, hiccup) of subcortical origin. Side-effects subsided after stopping the treatment anf posed no problem in the management of the patients. These findings confirm the usefulness and safety of the PG therapy and indicate that the intraaortic route of administration is preferable. 相似文献
4.
B.D. Rush K.F. Wilkinson N.M. Nichols R. Ochoa M.N. Brunden M.J. Ruwart 《Prostaglandins & other lipid mediators》1989,37(6)
Studies were conducted to assess the possible protective action of 16,16-dimethyl prostaglandin E2 (DMPG) against acute aflatoxin B1 (AFB1) induced hepatic injury in the rat. Evaluation of liver damage of histopathologic techniques and clinical chemistry indicated that hepatic necrosis was ameliorated by treatment with DMPG even though binding of radiolabeled (3H)-AFB1 to hepatic DNA was unaffected by this prostaglandin. However, DMPG did not protect rats against AFB1-induced mortality. These data suggest that hepatic protection by DMPG was due to mechanisms other than an interference with the activation or hepatic binding of AFB1. 相似文献
5.
T.L.S. Au G.A. Collins C.J. Harvie M.J.A. Walker 《Prostaglandins & other lipid mediators》1979,18(5):707-720
Prostaglandins E2 and I2 were compared with known antiarrhythmics for their actions against arrhythmias produced by occlusion of the left anterior descending coronary artery in the anaesthetised rat while PGI2 was also examined in the dog. PGI2 in the dog suppressed early arrhythmias produced during occlusion but did not influence those produced by occlusion-release or those occurring 24 hours after a permanent occlusion; none of the A,B,C or D series prostaglandins tested markedly reduced 24 hour arrhythmias. In the rat PGE2 was antiarrhythmic against early occlusion arrhythmias (30 minutes occlusion) in a dose related manner (infusions of 1–4 μg/kg/min) whereas PGI2 infusions potentiated the arrhythmogenic effect of occlusion. PGE2 was as effective an antiarrhythmic as 10mg/kg Org. 6001 which was more effective in this test situation than d1-propranolol. No obvious mechanisms for the actions of PGE2 or PGI2 were apparent although both agents lowered blood pressure and reduced the size of the occluded zone produced by ligation. 相似文献
6.
Prostaglandin E2 (PGE2) facilitated sexual behavior in estrogen-primed ovariectomized or ovariectomized-adrenalectomized rats. Administration of indomethacin, an inhibitor of prostaglandin synthesis, attenuated the effectiveness of estrogen and progesterone in inducing sexual receptivity in ovariectomized rats. Concurrent administration of PGE2 with indomethacin restored sexual behavior only when administered early in the estrogen-priming period but not if administered along with the progesterone. Our studies support the likelihood of a role of prostaglandins in the control of sexual behavior in the female rat. 相似文献
7.
The oxytocic properties of prostaglandin 16,16 dimethyl E2 methyl ester were investigated during the second trimester of pregnancy. As an abortifacient, this compound compared unfavorably to the 15 methyl analogs of prostaglandin E2, with a lower rate of effectiveness and a relatively high incidence of side effects. 相似文献
8.
Prostaglandins E1 (PGE1) and E2 (PGE2) have been coupled with the amine group of phosphatidylethanolamine (PE) by means of dicyclohexylcarbodiimide. These complexes basically mimic the relaxant and contractile effects of the corresponding free prostaglandins (PGs) on various smooth muscle preparations, but exhibit a delayed onset of action and a lower affinity for the PG receptors. The complexes are comparable with the free, parent PGs, in their intrinsic activities. The same holds true for the effects on blood pressure and on the motility of the uterus
. The PGE2-PE complex is hydrolysed to release obviously free PGE2 by cell-free homogenates prepared from various tissues, but not by blood plasma. The PGE2-PE complex is immunologically indistinguishable from the free PGE2. 相似文献
9.
Zahir Qureshi Lauren M. Cagen 《Biochemical and biophysical research communications》1982,104(4):1255-1263
Slices of rabbit renal medulla and rabbit renal papilla were incubated with a mixture of [1-14C]-arachidonic acid and [5,6,8,9,11,12,14,15-3H]-arachidonic acid. In both tissues, comparison of the isotope ratios of the radioactive products with the isotope ratio of the added arachidonic indicated that: (a) there was no discernable isotope effect in the biosynthesis of prostaglandin E2; (b) prostaglandin F2α was formed by reduction of prostaglandin H2 and not by reduction of prostaglandin E2; and (c) most of the radioactive product arose from arachidonic acid that had been incorporated into the tissue and not from the direct action of cyclooxygenase on arachidonic acid in the medium. 相似文献
10.
Prostaglandins PGE1 and PGE2 extracted from bovine semen, purified via silicic column chromatography were quantified by gas chromatography as their methoxime methyl ester trimethylsilyl ether derivatives. The PGE1 and PGE2 concentrations of 19 bovine semen samples ranged from 395 ± 225 and 487 ± 407 ng/ml, respectively. A constant 1:1 ratio between PGE1 and PGE2 was observed. There was no relationship between PGE and sperm motility, but high sperm counts were apparently associated with decreased PGE levels. The direct precursors of PGE1 and PGE2, i.e. 20:3n6 and 20:4n6, occurred in low concentrations compared to other related unsaturated fatty acids, i.e. 18:2n6 and 22:5n6 of the n-6 family. 相似文献
11.
Prostaglandins PGE1 and PGE2 extracted from bovine semen, purified via silicic column chromatography were quantified by gas chromatography as their methoxime methyl ester trimethylsilyl ether derivatives. The PGE1 and PGE2 concentrations of 19 bovine semen samples ranged from 395 ± 225 and 487 ± 407 ng/ml, respectively. A constant 1:1 ratio between PGE1 and PGE2 was observed. There was no relationship between PGE and sperm motility, but high sperm counts were generally associated with decreased PGE levels. The direct precursors of PGE1 and PGE2, i.e. 20:3n6 and 20:4n6, occurred in low concentrations compared to other related unsaturated fatty acids, i.e. 18:2n6 and 22:5n6 of the n-6 family. 相似文献
12.
Binding of biologically active 3H-PGE2 to particulate fractions of porcine gastrointestinal mucosa and muscle was investigated. Specific binding activity was detected in the 2500 xg and 30,000 xg sedimentation fractions of mucosa from esophagus, fundus, antrum, duodenum, ileum and colon, as well as in serosal muscle taken from the antrum, ileum, and colon. Optimal binding (> 40 fmol/mg protein) was observed in the 30,000 xg fraction of fundic mucosa incubated at pH 5.0. The characteristics of 3H-PGE2 binding were variable in the remainder of the gastrointestinal tract although binding in these tissues was significantly less (0.2 to 15 fmol/mg protein) than that observed in the fundic mucosa. These data suggest that the cellular and/or subcellular site of PG binding is not uniform throughout the gastrointestinal tract. In fundic mucosa removal of the surface epithelial layer by scraping did not significantly alter the total binding activity for PGE. This result suggests that in gastric secretory mucosa optimal binding activity for PGE2 occurs within the gastric pits deep to the surface epithelium. 相似文献
13.
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
14.
Donald E. Wilson I W. Chang John Paulsrud George Holland 《Prostaglandins & other lipid mediators》1978,16(1):121-126
11-Methyl 16,16 Dimethyl Prostaglandin E2 (TM-PGE2) at peak effectiveness inhibited acid output stimulated submaximally by histamine in the dog by 95 and 84% when administered by the intravenous and oral routes, respectively. Inhibition of secretion was maintained for
hours following intravenous administration while with the oral route, secretory inhibition was still present at the end of two hours after administration of the drug. The degree of inhibition of acid secretion caused by TM-PGE2, its duration of action and the lack of side effects observed following administration of this drug makes it a suitable compound for evaluation as an anti-secretory agent in man. 相似文献
15.
Donald E. Wilson M.D. Stephen L. Winter M.D. 《Prostaglandins & other lipid mediators》1978,16(1):127-133
11-Methyl 16,16 Dimethyl Prostaglandin E2 (TM-PGE) was administered orally to man in dosages of 2.5, 5, 7.5 and 10 μg/kg. Maximal inhibition of basal secretion was 52 and 78% and submaximal histamine-stimulated secretion 45 and 70% for volume and acid output, respectively. Secretory inhibition was observed for approximately two hours after ingestion of the drug. No effect was observed on serum gastrin levels. Side effects occurred with equal frequency in the placebo and drug groups. TM-PGE is well tolerated and inhibits both basal and submaximal histamine-stimulated acid secretion in man. Further evaluation may prove it to be helpful in the clinical treatment of acid hypersecretory states and peptic ulcer disease. 相似文献
16.
The object of this study was to examine the effects of exogenous and endogenous prostaglandin E2 (PGE2) on the sexual behavior of female South African clawed frogs, Xenopus laevis. Ticking and leg extension, which communicate sexual unreceptivity to males, were studied in intact, ovariectomized, and ovariectomized-oviductectomized females. The onset of the PGE2 behavioral effect occurs within 30 sec to 3 min of injection for intact and ovariectomized females; for ovariectomized-oviductectomized females, the latency period for the effect ranges from 10-20 min. PGE2 induced receptivity in doses as low as 0.03 microgram/frog. Injection of the prostaglandin synthesis inhibitors, indomethacin and flurbiprofen (FBP), blocked chorionic gonadotropin- (HCG-) induced behavioral receptivity, suggesting that endogenous prostaglandin synthesis may have a role in regulating female sexual behavior. Flurbiprofen blockade of HCG-induced receptivity was reversed by PGE2 administration, suggesting that FBP's effects are PG synthesis-specific. 相似文献
17.
Howard R. Knapp Oswald Oelz Brian J. Sweetman John A. Oates 《Prostaglandins & other lipid mediators》1978,15(5):751-757
Whole cell preparations of rat stomach corpus, jejunum, and colon were incubated and the released prostaglandin E2 (PGE2), PGF2α, PGD2, 15 keto-13,14 dihydro PGE2, and 15 keto-13,14 dihydro PGF2α were measured by combined gas chromatography-mass spectrometry. All regions made PGD2 and possessed a high capacity for producing 15 keto-13,14 dihydro derivatives of both PGE2 and PGF2α. Hypertonic sucrose solutions resulted in concentration-dependent increases in prostaglandin release, particularly of PGE2 and its metabolite. It is suggested that PG's may play a role in the local effects of luminal hyperosomolarity on digestive tract functions. 相似文献
18.
William F. Stenson Kathy Chang Joseph R. Williamson 《Prostaglandins & other lipid mediators》1986,32(1)
The activity of synthetic LTB4 and PGE2, in increasing vascular permeability was tested simultaneously in seventeen different organs in the rat. Rats were injected in the aortic arch through a cannula in the carotid artery with 125-I-albumin, 51Cr-erythrocytes, and 57Co-EDTA. The rats were then injected through the carotid artery cannula with LTB4, PGE2 or a combination of LTB4 and PGE2. Eight minutes later the rats were killed and the activity of 125I, 51Cr, and 57Co measured in different organs. Changes in vascular permeability were infered from changes in the ratios of the isotope activities. LTB4 (15 μg/kg) induced enhanced permeability in caecum, small bowel, skin, fat pad, stomach, pancreas, and aorta, but not in the heart, brain, colon, testes, diaphragm, forelimb, cremaster muscle, lung, kidney or eye. A lower dose of LTB4, 3 μg/kg, enhanced vascular permeability in caecum, small bowel, skin, stomach, and aorta. PGE2 (1 μg/kg) enhanced vascular permeability only in the caecum. A combination of LTB4 (3 μg/kg) and PGE2 (1 μg/kg) was more potent than either alone. Rats depleted of neutrophils with anti-neutrophil serum were less sensitive to LTB4 than intact rats. These findings suggest that the vasculatures of different tissues in the rat vary markedly in their susceptibility to LTB4 induced increases in permeability. 相似文献
19.
The effects of orally administered prostaglandin E2, 16,16-dimethyl prostaglandin E2 and U-46619, an analogue of the prostaglandin endoperoxide PGH2, on gastric secretory volume, acid and mucus were studied in the rat. All of the compounds significantly increased the volume of gastric secretion, mucus secretion, measured as N-acetylneuraminic acid and mucus synthesis measured as the incorporation of [3H]-glucosamine into mucosal glycoprotein; however, only PGE2 and 16,16-dimethyl PGE2 inhibited acid secretion. U-46619, 1.5 mg/kg provided significant protection against ethanol-induced gastric ulcers, an effect that has been previously shown for the other two compounds. These studies provide additional evidence that prostaglandin induced mucosal protection may by related to an effect on mucus and on stimulation of nonparietal cell gastric secretion. Further study of these parameters may be important in the development of antiulcer drugs for long term clinical use. 相似文献
20.
S. Aktan C. Aykut B.. Yegen U.
zkutlu I. Okar S. Ercan 《Prostaglandins, leukotrienes, and essential fatty acids》1992,46(4)
Prostaglandin E2 (PGE2) and leukotriene C4 (LTC4) are the metabolites of arachidonic acid (AA) that increase in forebrain following global ischemia and reperfusion. These mediators are highly potent vasoconstrictors of cerebral arteries leading to enhanced vascular permeability that induces the formation of vasogenic edema. In this study, after developing and experimental animal model simulating the concept of ischemic penumbra in the rat, the levels of PGE2 and LTC4 produced in the forebrain were measured and the effects of these mediators in short duration and prolonged reperfusion were investigated and then correlated with nueropathological findings. We found statistically significant reduction both in PGE2 and LTC4-like activities after just 10 min ischemia (p<0.05, p<0.05). PGE2-like activity significantly increased in the 4th and 60th min of reperfusion (p<0.05, p<0.05). In the 15th min of reperfusion, PGE2 was found to be significantly reduced (p<0.005) that may be due to the formation of free oxygen radicals by activation of PG hydroperoxidase reaction that inhibits PGE2 production in the cylooxygenase pathway. LTs were not significantly increased in any reperfused group. Inhibition of the lipoxygenase pathway of AA metabolism may occur as a result of 15-HPETE (15-hydroperoxyeicosatetraenoic acid) production. Pathologically, edema and degeneration of brain tissue were seen beginning from the 4th min of reperfusion that reached a peak in the 60th min of reperfusion which is in accordance with biochemical changes in the damaged tissue. It is concluded that by preventing the formation of AA metabolites in the early hours of ischemia and reperfusion, it could be possible to increase blood flow in the ischemic penumbra that should limit the infarct area. 相似文献