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1.
《Insect Biochemistry》1982,12(6):599-603
Prostaglandin E (PGE1 and PGE2) and prostaglandin F2α (PGF2α) are widely distributed in insects belonging to seven species representing six orders. Whole body concentrations range from 0.2 to 16 pg/mg protein. PGE and PGF2α are found in muscle but are not abundant in testicular tissue. In the house cricket, Acheta domesticus (L.), high prostaglandin levels in the testes and the female spermatheca are reduced in the presence of the prostaglandin synthesis inhibitors aspirin, acetaminophen and indomethacin. An interaction of the prostaglandins with cyclic GMP and cyclic AMP in cricket tissues was not observed using these inhibitors. The house cricket appears to be a model for studying prostaglandin function in insects. 相似文献
2.
《Prostaglandins and medicine》1978,1(5):397-410
The hamster cheek pouch prepared for intravital observations on macromolecular permeability with fluorescein labelled dextran was used in four series of 5 hamsters each, all pretreated with indomethacin. Bradykinin, PGE1, PGE2 and PGF2α increased macromolecular leakage at postcapillary venules, and this leakage was reversible on removal of agent. A linear relation was found between the logarithmic value of dose of bradykinin and the mean number of leakage sites. No tachyphylaxis to bradykinin was seen. The effect of either PGE1, PGE2 or PGF2α applied simultaneously with bradykinin was to significantly (p<0.05) potentiate the bradykinin response. Bradykinin and these prostaglandins appeared to have the same site of action for their effect of increasing permeability, e.g. the postcapillary venule. 相似文献
3.
Experiments were carried out in healthy male volunteers to investigate the effect of the inhalation of prostaglandin F2α (PGF2α) on airways resistance and the influence of the subsequent inhalation of prostaglandin E2 (PGE2). Airways resistance, which reflects the tone of smooth muscle in the larger airways in man, was measured by total body plethysmography.The inhalation of PGF2α (40-60 μg) caused an increase in airways resistance in all subjects. Both PGE2 (55 μg) and isoprenaline (550 μg) given by metered aerosol promptly reversed the bronchoconstriction induced by PGF2α, but isoprenaline was more effective in this respect.A role for these prostaglandins in the control of bronchial muscle tone is discussed. 相似文献
4.
《Prostaglandins, Leukotrienes and Medicine》1984,13(3):289-293
The 24 hour urinary excretion of 6-keto PGF1α and PGE2 was compared in 2 kidney-1 clip rats developing hypertension within 12 weeks of renal artery clipping with rats remaining normotensive over this period. Although systolic blood pressure was markedly elevated in the hypertensive (210 ± 5.1 mm Hg), in contrast with the normotensive (141 ± 1.9 mm Hg) group, urinary levels of 6-keto PGF1α (26.1 ± 3.4 and 22.1 ± 2.7 ng/24h, respectively) and PGE2 (52.8 ± 28 and 53.3 ± 10.8 ng/24h) were not significantly different. Treating the 2 kidney-1 clip normotensive group with indomethacin (3.0 mg/kg, by intraperitoneal injection) twice-weekly for 3 weeks reduced 6-keto PGF1α excretion from 22.1 ± 2.7 to 8.4 ± 2.2 ng/24h (P < 0.002) and PGE2 from 53.3 ± 10.8 to 8.7 ± 1.8 ng/24h (P < 0.002) but did not change blood pressure when compared with a similar group given buffer vehicle only. These findings do not support a role for renal prostaglandins in 2 kidney-1 clip hypertension in the rat. 相似文献
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We have shown earlier that prostacylin (PGI2) and its stable analogue: 7-oxo-prostacyclin(7-OXO) may induce a prolonged, late appearing (24–48 h after drug administration), dose dependent protection of the heart from harmful consequences of a subsequent severe ischaemic stress, such as myocardial ischaemia, life-threatening ventricular arrhythmias and early ischaemic morphological changes. In an other study we observed that a similar but shortlived (less than 1 h) cardioprotection, induced by preconditioning brief coronary artery occlusions, is greatly reduced by blockade of the cyclooxygenase pathway, suggesting that prostanoids might play a role in this shortlasting protection.Objective of our present study was to elucidate the importance of some arachidonic acid (AA) metabolites, such as PGI2 and thromboxane A2 (TXA2) in the mechanism of the late appearing, prolonged cardioprotection. Estimation of the metabolites: 6-keto-PGF1 (6-KETO) and thromboxane B2 (TXB2) was made from the perfusate of isolated Langendorff hearts of guinea-pigs pretreated with 50 g/kg 7-OXO, 24 and 48 h before preparation. Pretreatment alone produced a slight, but significant elevation of 6-KETO (from 206±11 to 284±19 pg/ml/min after 24 h, and to 261±18 pg/ml/min after 48 h). No change was seen in TXB2 production. Global ischaemia for 25 min (followed by 25 min reperfusion) markedly increased the release of both AA metabolites; maximal values were observed in the third min of reperfusion (6-KETO from 206±11 to 1275±55 pg/ml/min and TXB2 from 29±4 to 172±12 pg/ml/min). All values returned to the preischaemic level by the 25th min of reperfusion. Ischaemic increase in 6-KETO level was significantly higher in the perfusate of hearts from pretreated animals (1507±73 pg/ml/min after 24 h, and 1398±54 pg/ml/min after 48 h) that in those of untreated controls. There was no difference in TXB2 values. Thus both basal and ischaemic release of PGI2 increased 24 and 48 h after pretreatment with 7-OXO but not TXA2 production. Results suggest that endogenous prostanoids might play a role in late appearing cardioprotection. 相似文献
7.
The effects of several prostaglandins (PGs) injected through the subclavian artery toward the cardiac sympathetic ganglia of spinal dogs were studied by utilizing changes of the heart rate as indicator of ganglionic function. PGF2α (10–270 μg) administered intra-arterially in the presence or absence of preganglionic stimulation produced weak positive chronotropic effects, which were increased by physostigmine. This positive chronotropic effect of F2α after physostigmine was inhibited by hexamethonium plus atropine, and depressed after hemicholinium-3 except for the response elicited by the first dose of F2α. PGE1 and E2 injected during preganglionic stimulation did not affect the heart rate. Intra-arterially administered epinephrine and dopamine depressed dose-dependently transmission in the cardiac ganglia, the effect being inhibited by E1 and E2 but not by F2α. These results suggest that F2α facilitates the release of acetylcholine from preganglionic nerve ending, whereas E1 and E2 antagonize the inhibitory actions of catecholamine in the cardiac ganglia. 相似文献
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N. A. M. Wales 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1988,158(5):621-626
Summary Hagfish,Myxine glutinosa, were used in an investigation of the possible effects of various eicosanoids and the prostaglandin synthetase inhibitor indomethacin, on cortisol production, blood pressure control, urine flow and electrolyte balance.Cortisol levels in plasma of untreated control animals and plasma from animals 1 h following injection of 50 g kg–1 prostaglandin E1, E2, A2, F2 TXB2 and indomethacin were not detectable. However, plasma cortisol levels rose to between 10 and 26 pg ml–1 1 h following injection of either 50 g kg–1 arachidonic acid or prostaglandin E2. This rise was similar in magnitude to that produced 1 h following administration of 50 g kg–1 porcine ACTH.The resting dorsal aortic blood pressure of between 3.50 and 3.75 mmHg was reduced on average by 50% for 12–15 min when animals received 10 g kg–1 arachidonic acid, prostaglandin E1, E2, A2, and TXB2 and was effectively reduced to zero for 20 min or more following 50 g kg–1 of these eicosanoids. Similar doses of prostaglandin F2, however, evoked an increase in blood pressure (19–33%) whilst indomethacin was without effect.Control measurements of urine flow inMyxine were estimated to be between 540 and 660 l h–1 kg–1. There was a marked reduction in urine output following the arterial vasodepression induced by arachidonic acid, prostaglandin E1, E2, A2 and TXB2 in doses of 10 g kg–1, an effect which became even more pronouced following injection of 50 g kg–1 quantities, leading in some cases to complete anuria. There was no significant change in urine volume following either the vasopressor action of prostaglandin F2 or following indomethacin.None of the compounds tested in this study significantly influenced the plasma or urine electrolyte status ofMyxine. 相似文献
10.
Bahar Tunçtan Sedat Altuğ Orhan Uludağ Nurettin Abacioğlu 《Biological Rhythm Research》2013,44(4):499-513
Clinical features of certain immuno-inflammatory disorders exhibit time-dependent fluctuations, which could be related to circadian rhythmicity of proinflammatory mediator production. Many biologically active substances including nitric oxide (NO) and eicosanoids are released into the circulation in sepsis. Increased NO and eicosanoid levels have been reported to be responsible from death in septic shock. The aim of this study was to investigate the variations in the NO and eicosanoid production and mortality induced by bacterial endotoxin, lipopolysaccharide (LPS) injected either in the morning or in the evening. Experiments were performed on mice synchronised to 12 h light and 12 h dark (lights on at 09:00 h). Animals were injected intraperitoneally with LPS (10 mg/kg) at 09:00 (morning) and 21:00 h (evening) alone or in combination with aminoguanidine (NO synthase (NOS) inhibitor) (100 mg/kg) or indomethacin (cyclooxygenase (COX) inhibitor) (100 mg/kg). The serum was separated from blood samples obtained at nine different time points. Nitrite (stable product of NO), 6-keto-prostaglandin F1α (6-keto-PGF1α, stable product of prostacyclin) and thromboxane B2 (TxB2, stable product of thromboxane) concentrations in serum samples were measured. Serum nitrite levels showed a 24 h circadian rhythmicity depending on LPS injection time. Morning injection caused a peak after 15 h, while evening injection had two peaks after 9 and 18 h. The peak values obtained from morning and evening injections were significantly decreased by aminoguanidine and indomethacin. When LPS injected to mice in the morning and in the evening, it gradually increased the mortality rate within 24 h which could be abolished by aminoguanidine, but not indomethacin. Indomethacin-induced inhibition on LPS-induced nitrite levels was higher in the morning than in the evening. 6-keto-PGF1α and TxB2 levels were decreased by indomethacin when injected with LPS at both injection times, but not aminoguanidine. These results showed that there is an interaction between NO and eicosanoids, and LPS may produce different effects on NOS activity, but not eicosanoid production and mortality, depending on injection time in the experimental septic shock model in mice. Chronopharmacological manipulations of NOS and COX pathways and interactions between them could lead to novel therapeutic approaches for the treatment of septic shock. 相似文献
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《Prostaglandins & other lipid mediators》1986,32(5):691-701
Aspirin inhibits cyclo-oxygenase, thus preventing prostanoids formation. After oral administration aspirin is hydrolysed to inactive salicylate partly within the gastrointestinal tract, partly during first pass in the liver, partly in the circulation by plasma esterases. Intravenous aspirin, in contrast, mainly undergoes plasma esterase-catalysed deacetylation. Six healthy male subjects were given 1 g aspirin orally and intravenously two weeks apart according to a cross-over randomized design. Whereas serum T×B2 generation reflecting platelet cyclo-oxygenase activity was suppressed by aspirin by both routes, urinary excretion of T×B2 and 6-keto-PGF1α was not affected by oral aspirin, but was partially though significantly reduced by the i.v. drug. Drug disposition seems therefore to be essential in determining the “biochemical selectivity” of aspirin as related to platelet and renal prostanoids generation. 相似文献
13.
Treatment with PGF2α resulted in the termination of pregnancy in 16- and 19-day pregnant rats, but not in 10- or 13-day pregnant rats. Rats that aborted displayed a rapid onset of maternal behavior when tested with foster pups. Aborted rats also displayed sexual receptivity and ovulation: these phenomena resemble the sequence of events following hysterectomy on the same days of pregnancy. Both can be related to the events surrounding normal parturition in the rat. The results are interpreted as due to a pregnancy-induced deactivation of the factor in the uterus that prevents estrogen from stimulating maternal behavior in nonpregnant females. In the absence of this factor, the PGF2α-induced rise in estrogen secretion facilitates maternal behavior and sexual behavior and induces ovulation. 相似文献
14.
J M Gerrard 《Canadian journal of physiology and pharmacology》1989,67(8):922-928
The body's ability to produce prostacyclin and thromboxane by blood vessels and platelets may be important in hemostatic and thrombotic disorders and in blood pressure regulation. There are limitations to the information that can be derived from measurement of the active substances or metabolites in plasma and urine. Assays for thromboxane and prostacyclin in bleeding time blood reflect production in response to a single standardized vascular injury, and show considerable promise in furthering our understanding of the production of these chemicals in vivo. These assays may improve the assessment of risk of developing thrombotic disorders and improve the ability to monitor treatment. Studies to date have focused largely on the influences of various doses of aspirin on the production of prostacyclin and thromboxane in bleeding time blood, but also suggest that smokers are high thromboxane producers. In addition, individuals who exhibit type A behavior, a behavior pattern characterized by a relatively high level of ambitiousness, hostility, and competitive drive and a chronic sense of urgency appear to be low prostacyclin producers. Diets enriched in sunflower oil were found to diminish thromboxane production, while diets high in canola oil enhanced prostacyclin formation. 相似文献
15.
The inotropic and chronotropic actions of prostaglandin (PG) types PGE1, PGA1, and PGF2α were studied in isolated guinea pig right and left atria, and papillary muscles; rabbit atria; and toad ventricular strips in order to more completely define the cardiac contractile properties of PG. All three prostaglandins, in muscle bath concentrations of 10μg/ml, exerted positive inotropic and chronotropic actions on guinea pig atrium. These contractile effects were persistent after removal of PG from the muscle bath and appeared to limit the relative response to a subsequent dose of PG. The inotropic action of PGE1 was present over a wide range of bath calcium concentrations (1.1 to 4.4 mM/L). Beta adrenergic receptor blockade, histamine blockade, and pretreatment with reserpine failed to significantly affect the inotropic actions of PG. Norepinephrine and histamine produced more potent inotropic and chronotropic effects on guinea pig atria than did PG and these contractile effects did not exhibit persistence or tachyphylaxis. The prostaglandins did not significantly affect dose response curves for norepinephrine inotropic and chronotropic actions. The prostaglandins had no effect on the force or frequency of contraction in rabbit atria. PGE1 exerted a positive inotropic effect on toad ventricular myocardium whereas PGA1 had no effect and PGF2α had a negative inotropic action. 相似文献
16.
Daniele Castiglia Alessandro Cestelli Maria Scaturro Tommaso Nastasi Italia Di Liegro 《Neurochemical research》1994,19(12):1531-1537
Two overlapping rat cDNAs, covering a continuous region of 1107 base pairs, have been isolated and sequenced. The clones contain identical open reading frames, encoding a 136 amino acid long polypeptide which exhibits 100% identity to other mammalian H3.3 histone variants. We show that the inserts derive, in particular, from the H3.3B gene. We used these inserts and an insert from an H1° encoding clone, previously described (6), as probes to study the accumulation of mRNAs encoding the corresponding histone replacement variants (namely, H1° and H3.3) during rat brain development. We found that the concentration of both H1° and H3.3B mRNAs decreases from the embryonal day 18 (E18) to the postnatal day 10 (P10), with inverse correlation to protein accumulation.This paper is dedicated to our friend Paolo Carbone who devoted his life to research and teaching in Genetics. We will always remember him for scientific honesty and for his unique qualities of humanity. 相似文献
17.
M.V. Dunn N.G. Humphries G.R. Judkins June Z. Kendall G.W. Knight 《Prostaglandins & other lipid mediators》1973,3(4):509-514
Intraperitoneal administration of anti-PGF2α antibody in pregnant rats on Day 17 lengthened the duration of pregnancy by 24 hours. Prenatal vaginal bleeding was a common feature suggesting that parturition was prolonged. These observations support a role for prostaglandin F2α in the events leading to parturition in the rat. 相似文献
18.
《Prostaglandins and medicine》1981,6(4):359-368
The production of prostaglandins (PGs) E and F and 6-keto PGF1α was investigated by using human decidua, amnion, and pregnant myometrium obtained before and after onset of labor, and human nonpregnant myometrium collected during luteal phase. PGs produced were measured by radioimmunoassay developed in our laboratory. The radioimmunoassay for 6-keto PGF1α is specific and accurate. PGE was formed at an almost constant rate regardless of the condition under which the three tissues tested were obtained, with the amnion showing the highest activity compared with decidua and myometrium. PGF production increased remarkably during labor in the myometrium and decidua but not in the amnion. In the myometrium during labor, PGF levels were three times higher than before labor. The pregnant myometrium produced more PGs than the nonpregnant myometrium. The production of 6-keto PGF1α, a stable, nonenzymatically formed derivative of PGI2, was observed to be much higher in the pregnant myometrium than in decidua, amnion, or nonpregnant myometrium. Contrary to the pattern of PGF production, 6-keto PGF1α was lower during labor. The physiological significance of PG production by decidua, amnion, and myometrium in relation to parturition is discussed. 相似文献
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Both intact cortical tissue and isolated cortical cells from the adrenal gland of the rat were analyzed for 6-keto-PGF1α, the hydrolysis metabolite of PGI2, using high-performance liquid chromatography and gas chromatography-mass spectrometry. 6-Keto-PGF1α was present in both incubations of intact tissue and isolated cells of the adrenal cortex, at higher concentrations than either PGF2α or PGE2. Thus, the cortex does not depend upon vascular components for the synthesis of the PGI2 metabolite. Studies , using isolated cortical cells exposed to 6-keto-PGF1α (10?6-10?4M), show that this PG does not alter cAMP levels or steroidogenesis. Cells exposed to PGI2 (10?6-10?4M), however, show a concentration-dependent increase of up to 4-fold in the levels of cAMP without altering corticosterone production. ACTH (5–200 μU/ml) increased cAMP levels up to 14-fold, and corticosterone levels up to 6-fold, in isolated cells. ACTH plus PGI2 produced an additive increase in levels of cAMP, however, the steroidogenic response was equal to that elicited by ACTH alone. Adrenal glands of the rat perfused with PGI2 showed a small decrease in corticosterone production, whereas ACTH greatly stimulated steroid release. Thus, while 6-keto-PGF1α is present in the rat adrenal cortex, its precursor, PGI2, is not a steroidogenic agent in this tissue although it does stimulate the accumulation of cAMP. 相似文献