Search results for "prostaglandin"
showing 10 items of 232 documents
Perioperative pupil size in low-energy femtosecond laser-assisted cataract surgery
2020
Purpose To assess potential changes in pupil size during femtosecond laser-assisted cataract surgery (FLACS) using a low-energy laser system. Methods The pupil sizes of eyes undergoing FLACS were measured using the Ziemer LDV Z8 by extracting images from the laser software after each of the following steps: application of suction, lens fragmentation, and capsulotomy. Furthermore, the pupil diameters were measured based on preoperative surgical microscope images and after releasing the suction. Paired t-test and the two one-sided tests (TOST) procedure were used for statistical analyses. The horizontal and vertical pupil diameters were compared in each of the steps with preoperative values.…
The specificity of prostaglandin E2 (PGE2) in reducing coronary vascular resistance: A comparison with adenosine.
1978
Experiments were performed on the isolated, electrically driven guinea-pig heart, perfused at constant rate. All animals were pretreated with reserpine. Myocardial contractile force (MCF), coronary perfusion pressure (CPP) and myocardial oxygen consumption (QO2) were monitored continuously. Both adenosine (ADO) and PGE2 produced a concentration-dependent decrease in the CPP. The ED50 (50% of maximum response) was 2.1 +/- 0.6 X 10(-9)M for PGE2 but 40 +/- 7 X 10(-9)M for ADO (P less than 0.01) at 1.8 mM Ca(e). This coronary vasodilation was independent of the external Ca-concentration, which was varied between 0.55-9.0 mM. PGE2 had no effect on MCF or QO2 and the effect of ADO was only sligh…
Prostaglandin E2 receptors and COX enxymes in human hepatocellular carcinoma: role in the regulation of cell growth
2008
The aim of this study was to investigate the expression of prostaglandin E 2 receptors (EP 1-4 ), cyclooxygenase-1 (COX-1), and COX-2 in nontumor and tumor human liver tissues, and also to evaluate the antitumor activity of selective EP 1 receptor antagonist used alone or in combination with COX-1 and COX-2 selective inhibitors. Semiquantitative PCR analyses revealed that EP 1-4 , COX-1, and COX-2 mRNA expression was detected in nearly all the tissue samples assayed, although with a high variability between nontumor and tumor tissues. In vitro EP 1 receptor antagonist inhibited anchorage-independent cell growth and reduced the viability of hepatocellular carcinoma (HCC) cells in a dose-depe…
Modulation of adrenergic contraction of dog pulmonary arteries by nitric oxide and prostacyclin.
1999
Abstract The aim of this work was to investigate the influence of endothelium-derived nitric oxide and prostaglandins on the contractile responses of isolated dog pulmonary arteries to electrical field stimulation and noradrenaline. Electrical field stimulation (1–8 Hz, 20 v, 0.25 ms duration, for 30 s) produced frequency-dependent contractions that were abolished by tetrodotoxin, guanethidine and, prazosin (all at 10−6 M). Noradrenaline induced concentration-dependent contractions with an EC50 of 1.85 × 10−6 M. The increases in tension induced by electrical stimulation and noradrenaline were of greater magnitude in arteries denuded of endothelium. In segments with endothelium, NG-nitro- l …
Contribution of endothelin receptors and cyclooxygenase-derivatives to the altered response of the rabbit renal artery to endothelin-1 in diabetes
2006
Abstract The influence of diabetes on regulatory mechanisms and specific receptors implicated in the response of isolated rabbit renal artery to endothelin-1 was examined. Endothelin-1 induced a concentration-dependent contraction that was less potent in arteries from diabetic rabbits than in arteries from control rabbits. Endothelium removal or NG-nitro- l -arginine (L-NOARG) enhanced contractions to endothelin-1 either in control and diabetic arteries. Indomethacin inhibited endothelin-1-induced response in control arteries, but enhanced it in diabetic arteries. In contrast to that observed in rubbed and in L-NOARG treated arteries, in the presence of indomethacin the contractile action o…
The effect of postsurgical administration of a selective cyclo-oxygenase-2 inhibitor on the healing of intrabony defects following treatment with ena…
2003
Regenerative treatment with enamel matrix proteins (EMD) has been shown to promote regeneration in intrabony periodontal defects. However, up to now various postoperative regimens such as the routine administration of nonsteroidal anti-inflammatory drugs (NSAIDs) were often used in combination with enamel matrix proteins. Therefore, it cannot be excluded that the results might have been influenced by the effect of the postoperative medication. The aim of this randomized, controlled, blinded, clinical investigation was to determine the effect of postsurgical administration of a selective cyclo-oxygenase-2 inhibitor on the healing of intrabony periodontal defects following regenerative period…
Effects of zinc acexamate on blood flow and prostanoid levels in the gastric mucosa of the rat
1989
The effects of the new antiulcer compound zinc acexamate on blood flow and prostanoid levels in the gastric mucosa have been studied. Zinc acexamate (30 and 300 mg/kg) dose-dependently prevents the reduction induced by the perfusion of noradrenaline (3.5 micrograms/kg.min, 30 min) in gastric mucosal blood flow, as measured by 3H-aniline clearance. Zinc acexamate pretreatment also increases the levels of prostaglandin E2 in the gastric mucosa of the rat, both under control conditions and after infusion with noradrenaline. The levels of thromboxane A2 and prostacyclin were not modified by zinc acexamate. These results confirm the importance of microcirculation in pathogenesis and the idea tha…
Beta-adrenoceptors mediate inhibition of [3H]-acetylcholine release from the isolated rat and guinea-pig trachea: role of the airway mucosa and prost…
1994
1. Rat or guinea pig isolated tracheae were labelled with [3H]-choline to measure evoked tritium outflow, which reflects neuronal release of [3H]-acetylcholine. Tritium outflow was evoked either by electrical stimulation of the extrinsic vagal nerve (rat tracheae) or by 27 mM potassium (guinea pig tracheae). 2. In rat tracheae isoprenaline (0.01, 0.1 microM) inhibited evoked [3H]-acetylcholine release, whereas beta 2-adrenoceptor-selective agonists (fenoterol, formoterol, salbutamol) were ineffective. 3. The inhibitory effect of isoprenaline was abolished under the following conditions: (i) presence of propranolol (1 microM) or of the beta 1-selective antagonist CGP 20712 A (0.1 microM); (i…
Brinzolamide/brimonidine fixed-dose combination bid as an adjunct to a prostaglandin analog for open-angle glaucoma/ocular hypertension.
2019
Purpose: To evaluate the additive intraocular pressure–lowering effect of twice-daily brinzolamide 1%/brimonidine 0.2% fixed-dose combination (BBFC) as an adjunct to a prostaglandin analog (PGA) in patients with open-angle glaucoma or ocular hypertension insufficiently controlled with PGA monotherapy. Methods: In this Phase 4, double-masked trial, patients aged ⩾18 years, with a mean intraocular pressure of ⩾19 and <32 mm Hg in at least one eye were randomized (1:1) to receive BBFC + PGA ( n = 96) or vehicle + PGA ( n = 92) for 6 weeks. The primary endpoint was the mean change in diurnal intraocular pressure from baseline (averaged over 09:00 and 11:00 h) at Week 6. Results: The mean diu…
ACTIONS OF PROSTAGLANDIN E2 ON MYOCARDIAL MECHANICS, CORONARY VASCULAR RESISTANCE AND OXYGEN CONSUMPTION IN THE GUINEA-PIG ISOLATED HEART PREPARATION
1975
Abstract 1 In isolated, electrically driven (3 Hz) hearts of guinea-pigs the action of prostaglandin E2 on left ventricular pressure (LVP), oxygen consumption (Qo2) and coronary vascular resistance (CVR) was studied by establishing cumulative concentration-response curves. The hearts were perfused at a constant flow (10 ml/min) with Tyrode solution (Ca++ 1.8 mM) at 32 degrees C. 2 Under control conditions prostaglandin E2 (2.86 X10(-11) -1.43 X 10(-7) M) decreased LVP, QO2 and CVR in a concentration-dependent manner by maximally 27, 18 and 38%, respectively (P less than 0.05). 3 After reserpine pretreatment there were lower initial values for all parameters measured. The effect of prostagla…