Search results for "PROSTAGLANDIN"
showing 10 items of 232 documents
V2-receptor–mediated relaxation of human renal arteries in response to desmopressin
1999
The effects of deamino-8-D-arginine vasopressin (desmopressin), a V2 receptor antidiuretic agonist, were studied in isolated rings from branches of renal arteries obtained from 22 patients undergoing nephrectomy. The rings were suspended in organ bath chambers for isometric recording of tension. In precontracted rings with norepinephrine (10(-6) to 3 x 10(-6) mol/L), desmopressin (10(-11) to 3 x 10(-7) mol/L) caused endothelium-dependent relaxation (81%+/-4% reversal of the initial contraction in arteries with endothelium; 20%+/-4% in arteries without endothelium; P < .05). The relaxation to desmopressin in rings with endothelium was reduced significantly by indomethacin (10(-6) mol/L) and …
Endothelium-dependent relaxation of human saphenous veins in response to vasopressin and desmopressin
1997
Purpose: The goal of this study was to determine the effects of vasopressin and the selective V 2 -receptor agonist desmopressin on human saphenous veins, with special emphasis on endothelium-mediated responses. Methods: Human saphenous vein segments were obtained from 35 patients undergoing coronary bypass surgery. Paired segments, one normal and the other deendothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. Concentration-response curves to vasopressin and desmopressin were determined in the presence and in the absence of either the V,-receptor antagonist d(CH 2 ) 5 Tyr(Me)AVP (10 −6 mol/L), the V 1 -V 2 receptor antagonist desGly-d(CH 2 ) 5 D-T…
The effects of prostaglandin F2α in the human eye
1985
The ocular effects of 200 micrograms of topically applied prostaglandin F2 alpha were studied in 18 nonglaucomatous volunteers. A fall in intraocular pressure was seen in the prostaglandin-treated eyes when compared with the placebo-treated control eyes. The maximum intraocular pressure reduction was observed at the 7th h and hypotensive ocular effect persisted for 24 h. Prostaglandins did not produce any change in pupillary diameter or signs of intraocular inflammation visible by anterior segment biomicroscopy or iris fluorescein angiography. The drug caused side effects: conjunctival hyperemia was constant and many patients complained of ocular smarting and headache. It could be useful in…
New Immunohistologic Findings on the Differential Role of Cyclooxygenase 1 and Cyclooxygenase 2 in Nasal Polyposis
2005
Background Cyclooxygenase 1 (Cox-1) plays a key role in arachidonic acid metabolism and in the pathophysiology and immunology of nasal polyposis in patients suffering from aspirin intolerance. We hypothesize that Cox-2 also might be relevant in the etiology of nasal polyps of aspirin-tolerant patients by their effects on inflammatory mediators as well as on microvascular permeability. Methods Fifty-two surgical specimens were immunohistochemically labeled for Cox-1 and Cox-2. Specimens were taken from chronically inflamed mucosa (n = 19) and from nasal polyps (n = 19) during endonasal sinus surgery. Controls were obtained from healthy nasal respiratory mucosa (n = 14), harvested during turb…
Comparison of the anticonstrictor action of dihydropyridines (nimodipine and nicardipine) and Mg2+ in isolated human cerebral arteries.
1992
The isometric tension recorded from ring segments of branches of human middle cerebral artery was the parameter used to study the inhibition of spasmogen-induced contractions as model for cerebral vasospasm. Concentration-response curves to 5-hydroxytryptamine (10(-9)-3 x 10(-5) M) and prostaglandin F2 alpha (10(-7)-3 x 10(-5) M) were inhibited in Ca(2+)-free medium and in Ca(2+)-free medium to which EGTA (1 mM) had been added, respectively. Nimodipine (10(-7), 10(-5) M), nicardipine (10(-7), 10(-5) M) and Mg2+ (magnesium sulfate 10(-4), 10(-2) M) inhibited the 5-HT-elicited contractions, and this inhibition was similar for the highest concentrations tested. In contrast, nimodipine and nica…
Polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein are associated with chronic spontaneous urticaria and urinary leukotriene E4
2011
The mechanisms of chronic spontaneous urticaria (CSU) continue to be unknown. Our working hypothesis is that polymorphisms of cyclo-oxygenases and 5-lipo-oxygenase-activating protein may be involved in the pathways leading to CSU. We examined five candidate polymorphisms of cyclo-oxygenases 1 and 2 and of 5-lipo-oxygenase-activating protein in 109 controls and in 94 CSU patients from Northern Italy. We also examined the levels of urinary leukotriene E4 (LTE4) before and after challenge with ASA. A multiple regression model was found to show that COX-2 5'UTR T/G, COX-2 Exon 10 T/C, and FLAP -336 G/A polymorphisms were significantly associated with CSU, with the minor allele more represented …
Increased prostaglandin E2 concentrations and cyclooxygenase-2 expression in asthmatic subjects with sputum eosinophilia.
2003
Abstract Background Prostaglandin E 2 (PGE 2 ) is known to be produced within human airways, but it is not clear whether in airway diseases it can play a deleterious or a beneficial role. Recently it has been reported that PGE 2 can enhance eosinophil survival in vitro. Objective To evaluate whether the concentrations of PGE 2 in asthmatic airways correlate with the number of eosinophils and can be responsible for eosinophil-enhanced survival and to identify the cyclooxygenase isoform contributing to the synthesis of PGE 2 by cells present in asthmatic airways. Methods Reversed-phase high-performance liquid chromatography and/or specific radioimmunoassay was used to measure PGE 2 concentrat…
The exposure of healthy volunteers to 200 ppm 1,1,1-trichloroethane increases the concentration of proinflammatory cytokines in nasal secretions
1999
Objectives: Irritating effects of organic solvents have usually been measured by means of questionnaires. The aim of the present study was to evaluate the sensitivity of different methods of detecting subclinical irritating effects. Methods: Twelve healthy, non-smoking students were exposed to 200 ppm and to 20 ppm 1,1,1-trichloroethane in an exposure chamber, using a crossover design. The amounts of interleukins (IL)-1β, IL-6 and IL-8 and prostaglandin E2 (PGE2) in nasal secretions were measured. Mucociliary transport time was determined with the saccharine test. Ciliary beat frequency of nasal epithelial cells was measured with video-interference contrast microscopy. Subjective symptoms w…
Relaxation induced by milrinone and rolipram in human penile arteries and veins
2002
Abstract We studied the relaxant effects of milrinone, an inhibitor of phosphodiesterase 3, and rolipram, an inhibitor of phosphodiesterase 4, on contracted human penile dorsal artery and deep dorsal vein. Vascular rings from 12 multi-organ donors were suspended in organ baths for isometric recording of tension. Both milrinone and rolipram inhibited (100%) the contraction induced by noradrenaline and shifted the relaxation–response curves to the cAMP forming agents prostaglandin E1 and forskolin to the left. The findings indicate that the cAMP pathway appears to be a main determinant of relaxation in human penile vessels.
The Effects of Prostaglandin E-1 in Patients with Intermittent Claudication
2006
Aim of the study is to evaluate the effects of Prostaglandin E-1 (PGE-1) in patients with peripheral arterial disease (PAD) at the 2nd b stage Fontaines classification. The study, controlled, single blinded, enrolled 123 patients with intermittent claudication that were randomised in two groups; the first group received a treatment with PGE-1 while the second one received a pentoxifylline-buflomedil association by venous infusion. We evaluated: Pain Free Walking Distance (PFWD), Maximum Walking Distance (MWD), Rest Flow (RF), Peak Flow (PF), Basal (BVR) and Minimal Vascular Resistance (MVR) with a strain gauge plethysmograph, Resting Flow (RF), Peak Flow (PF), time to reach the Peak Flow (t…