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Annals of Surgery Apr 1988Prostaglandin E2 (PGE2) reportedly increases protein break-down in skeletal muscle. The role of PGE2 for accelerated muscle proteolysis during sepsis, however, is...
Prostaglandin E2 (PGE2) reportedly increases protein break-down in skeletal muscle. The role of PGE2 for accelerated muscle proteolysis during sepsis, however, is controversial. In this study, the effect of the prostaglandin synthesis inhibitor indomethacin on PGE2 release and protein breakdown in skeletal muscle from nonseptic and septic rats was evaluated. Sepsis was induced in male Sprague-Dawley rats (40-60 g) by cecal ligation and puncture (CLP). After 16 hours the extensor digitorum longus (EDL) and soleus (SOL) muscles were dissected with intact tendons and incubated in an oxygenated medium, and the release of tyrosine (protein breakdown) and PGE2 into the incubation medium was determined. Paired muscles were incubated in the absence or presence of indomethacin (3 mumol/L or 6 mumol/L). In some experiments the effect of indomethacin was investigated in the presence of different concentrations of insulin (1, 10, or 100 mU/mL) since previous reports suggested an interaction between insulin and prostaglandins on protein turnover in skeletal muscle. In other experiments muscles were incubated in a flaccid or stretched state, which is known to influence the metabolic response to different substances. Protein breakdown rate was 0.210 +/- 0.013 and 0.492 +/- 0.025 mumol Tyr/g X 2 hours in EDL from nonseptic and septic rats, respectively (p less than 0.01). The corresponding values for SOL were 0.480 +/- 0.037 and 0.712 +/- 0.039 mumol Tyr/g X 2 hours (p less than 0.01). Addition of indomethacin to the incubation medium reduced PGE2 release from 29.1 +/- 3.1 to 6.8 +/- 0.7 ng/g X 2 hours in nonseptic SOL and from 50.6 +/- 10.4 to 5.6 +/- 0.7 ng/g X 2 hours in septic SOL. Protein breakdown rate in SOL and EDL from sham-operated or septic rats was unaffected by indomethacin, both when muscles were incubated in a flaccid or stretched state, and when they were incubated in the presence or absence of insulin. The present results do not suggest a role of PGE2 for accelerated muscle proteolysis in the present experimental septic model.
Topics: Animals; Bacterial Infections; Dinoprostone; Indomethacin; Male; Muscle Proteins; Muscles; Prostaglandins E; Rats; Rats, Inbred Strains; Tyrosine
PubMed: 3162671
DOI: 10.1097/00000658-198804000-00005 -
British Heart Journal Apr 1981
Topics: Adolescent; Adult; Blood Pressure; Cardiac Output; Female; Hemodynamics; Humans; Infusions, Parenteral; Myocardial Contraction; Pregnancy; Prostaglandins E; Prostaglandins F; Systole
PubMed: 7225258
DOI: 10.1136/hrt.45.4.447 -
Proceedings of the National Academy of... Jun 1978Antibodies that recognized the prostaglandin (PG) E structure were elicited from rabbits. 9-Deoxy-9-methylene-PGF2alpha, a stable isosteric mimic of PGE2, was conjugated...
Antibodies that recognized the prostaglandin (PG) E structure were elicited from rabbits. 9-Deoxy-9-methylene-PGF2alpha, a stable isosteric mimic of PGE2, was conjugated to two different protein immunogens and the immune response system was duped into producing antibodies with poor recognition for prostaglandins other than the hapten mimic (9-deoxy-9-methylene-PGF2alpha) and its isosteric counterparts (PGE1 and PGE2). With this procedure, crossreaction that would ordinarily arise from the chemical or metabolic instability of an authentic PGE2 immunogen was avoided. Antibodies raised against a keyhole limpet hemocyanin conjugate of 9-deoxy-9-methylene-PGF2alpha had an average intrinsic association constant, Ko = 2.6 X 10(9) liters.mole-1, for PGE2. Crossreaction was low for a number of related prostaglandins, and a sensitive radioimmunoassay procedure with a detection limit of 6 pg was developed.
Topics: Animals; Antibody Specificity; Carrier Proteins; Cross Reactions; Haptens; Hemocyanins; Molecular Conformation; Prostaglandins E; Prostaglandins F; Rabbits; Radioimmunoassay
PubMed: 275836
DOI: 10.1073/pnas.75.6.2689 -
Annals of the Rheumatic Diseases Oct 1981
Review
Topics: Arthritis, Rheumatoid; Blood Proteins; Cell Communication; Cells, Cultured; Collagen; Connective Tissue; Dinoprostone; Humans; Microbial Collagenase; Monocytes; Monokines; Parathyroid Hormone; Prostaglandins E; Synovial Membrane
PubMed: 6272658
DOI: 10.1136/ard.40.5.433 -
The Biochemical Journal Nov 1974Cyclic AMP levels per mg of cell protein were higher in late-passage (senescent) fibroblasts than in early-passage (young) fibroblasts both during growth and stationary...
Adenosine 3': 5'-cyclic monophosphate in young and senescent human fibroblasts during growth and stationary phase in vitro. Effects of prostaglandine E1 and of adrenaline.
Cyclic AMP levels per mg of cell protein were higher in late-passage (senescent) fibroblasts than in early-passage (young) fibroblasts both during growth and stationary phase, but, because the protein concentration per unit volume in senescent cells was lower than in young cells, the molar concentrations of intracellular cyclic AMP were very similar in the two cell types. In both young and senescent fibroblasts cyclic AMP levels declined during growth and no increase in intracellular cyclic AMP occurred in association with density-dependent inhibition of growth. These results indicate that changes in cyclic AMP concentration do not play a role in controlling the growth or in the senescent decline of human fibroblasts. Prostaglandin E(1) (1mum) caused maximal increases in fibroblast cyclic AMP concentration of 60-500-fold after 10-30min, and adrenaline (epinephrine) (10mum) caused maximum increases of 5-25-fold after 2-10min, depending on both the number of passages and the period after subculture. The cyclic AMP level in confluent young cells increased more with prostaglandin E(1) and far less with adrenaline than the cyclic AMP level in confluent senescent cells. During growth to confluence the cyclic AMP response to adrenaline declined in young cells and increased in senescent cells. As these responses to prostaglandin E(1) and to adrenaline changed independently of each other and of the basal cyclic AMP concentration, it is suggested that the expression of hormone receptors is altered both during growth to confluence and during senescence of human fibroblasts.
Topics: Adult; Cells, Cultured; Cyclic AMP; Epinephrine; Fibroblasts; Humans; In Vitro Techniques; Male; Prostaglandins E; Receptors, Cell Surface
PubMed: 4376959
DOI: 10.1042/bj1440253 -
Fertility and Sterility May 1984Prostaglandins E, F, 19-hydroxy E, and 19-hydroxy F (PGE, PGF, 19-OH-PGE, and 19-OH-PGF) in human semen were determined by a new chemical method. The method allows... (Comparative Study)
Comparative Study
Prostaglandins E, F, 19-hydroxy E, and 19-hydroxy F (PGE, PGF, 19-OH-PGE, and 19-OH-PGF) in human semen were determined by a new chemical method. The method allows liquefaction to occur, a prerequisite for simultaneous estimation of PG concentration and sperm characteristics in the same ejaculate. The present study showed also that the variation in PG concentration between different individuals was more pronounced than in repeated ejaculates from the same individual. Sperm density and sperm motility seemed related to PG concentration. A high density was associated with a low PG concentration. The concentration of 19-OH-PGE was higher and that of 19-OH-PGF lower in ejaculates with a normal sperm motility than in those with an abnormal motility. It seems that functional requisites of sperm depend upon optimal seminal PG concentration.
Topics: Alprostadil; Dinoprost; Humans; Male; Prostaglandins E; Prostaglandins F; Semen; Sperm Count; Sperm Motility; Time Factors
PubMed: 6546921
DOI: 10.1016/s0015-0282(16)47843-x -
The Journal of Biological Chemistry Apr 1988Tumor necrosis factor-alpha (TNF) is a macrophage-derived peptide that is known to be an important mediator in various physiologic and immunologic events. Although the...
Tumor necrosis factor-alpha (TNF) is a macrophage-derived peptide that is known to be an important mediator in various physiologic and immunologic events. Although the effector function of TNF has received recent attention, there is relatively little information regarding factors that regulate TNF expression. Highly Ia-positive murine peritoneal macrophages obtained via complete Freund's adjuvant elicitation were challenged with lipopolysaccharide (LPS) and assessed for the production and regulation of TNF at the cellular and molecular levels. In response to 1 microgram/ml LPS, the kinetics of functionally active TNF reached a maximum at approximately 3-4 h. The plateau in TNF levels was concomitant with an accelerated increase in prostaglandin E2 production. The addition of exogenous PGE2 demonstrated a dose-dependent reduction in LPS-induced TNF activity at the cellular level, as well as a significant reduction in TNF mRNA accumulation as assessed by Northern blot and in situ hybridization analysis. The reduction in LPS-stimulated mRNA accumulation by PGE2 was shown to occur at least at the level of transcription, since nuclear run-off analysis showed a specific reduction in TNF transcripts. These studies demonstrate that PGE2 can regulate macrophage-derived TNF gene expression.
Topics: Animals; Dinoprostone; Dose-Response Relationship, Drug; Gene Expression Regulation; Kinetics; Lipopolysaccharides; Macrophages; Mice; Nucleic Acid Hybridization; Prostaglandins E; RNA, Messenger; Tumor Necrosis Factor-alpha
PubMed: 3162731
DOI: No ID Found -
British Medical Journal (Clinical... Dec 1982The effects of prostaglandin E1 infusion on nailfold capillary haemodynamics were studied in eight patients with Raynaud's phenomenon secondary to progressive systemic...
The effects of prostaglandin E1 infusion on nailfold capillary haemodynamics were studied in eight patients with Raynaud's phenomenon secondary to progressive systemic sclerosis. Using a modified Landis microinjection technique the mean (+/- SEM) transcapillary pressure gradient was increased during and six weeks after infusion by 13.9 +/- 3.2 cm H2O (p less than 0.05) and 5.5 +/- 2.5 cm H2O (p less than 0.05) respectively. Capillary red cell velocity measured in two patients by video television microscopy also increased during and after infusion with prostaglandin E1. Six patients claimed subjective benefit and in three their ulcers healed. These findings support the observed beneficial effect of prostaglandin E1 and suggest that it improves the nutritive capillary circulation by lowering precapillary resistance.
Topics: Adult; Aged; Alprostadil; Blood Flow Velocity; Capillaries; Female; Fingers; Humans; Male; Middle Aged; Prostaglandins E; Raynaud Disease; Regional Blood Flow; Scleroderma, Systemic
PubMed: 6816332
DOI: 10.1136/bmj.285.6356.1688 -
Japanese Journal of Pharmacology Feb 1978Effects of intracerebroventricularly (i.c.v.) injected PGE2 and PGF2alpha on the urine outflow were studied in ethanol-anesthetized rats. PGE2 and PGF2alpha, when...
Effects of intracerebroventricularly (i.c.v.) injected PGE2 and PGF2alpha on the urine outflow were studied in ethanol-anesthetized rats. PGE2 and PGF2alpha, when injected i.c.v., caused diuresis which was followed by antidiuresis. Phentolamine, when perfused i.c.v., was an antidiuretic and inhibited the diuretic and antidiuretic effects of PGE2. Diphloretin phosphate inhibited both effects of PGE2. Polyphloretin phosphate (PPP) and propranolol blocked completely the PGE2-induced diuresis and consequently remarkable antidiuresis was observed after the combined treatments with PGE2 and PPP or propranolol. When PGE2 was perfused i.c.v., a sustained diuresis was obtained and antidiuretic effects of noradrenaline, gamma-aminobutyric acid and L-glutamate were potentiated, inhibited and unaffected by the perfusion with PGE2, respectively. It was indicated that the antidiuretic effect of PGE2 could be dissociated from the diuretic effect and that both effects were mediated through adrenergic mechanisms. The present result also suggested that central PGE2 might act as a modulator of some neurotransmitters involved in water metabolism.
Topics: Animals; Diuresis; Injections, Intraventricular; Male; Norepinephrine; Phentolamine; Prostaglandins E; Prostaglandins F; Rats; Time Factors; gamma-Aminobutyric Acid
PubMed: 651014
DOI: 10.1254/jjp.28.33 -
Japanese Journal of Pharmacology Jun 1981
Topics: Animals; In Vitro Techniques; Kidney Medulla; Male; Prostaglandins E; Prostaglandins F; Rats; Rats, Inbred Strains; Theophylline
PubMed: 7311163
DOI: 10.1254/jjp.31.477