Search results for "Prostacyclin"

Treatment of pulmonary hypertension in patients undergoing cardiac surgery with cardiopulmonary bypass: a randomized, prospective, double-blind study

2006

Pulmonary hypertension can already be present in patients undergoing cardiac surgery or can be exacerbated by cardiopulmonary bypass. Postoperative treatment is still a challenge for physicians. The aim of this study was to evaluate the effects of inhaled prostacyclin (iPGI2) and nitric oxide (iNO) compared with those of intravenous vasodilators.This prospective, randomized, double-blind study included 58 patients affected by severe mitral valve stenosis and pulmonary hypertension with high pulmonary vascular resistance (250 dynes x s x cm(-5)) and a mean pulmonary artery pressure25 mmHg. All patients were monitored by central venous, radial arterial and Swan-Ganz catheters. Data were recor…

Platelet Aggregation, Coagulation and Fibrinolysis at Rest and after Bicycle Ergometer Test in CHD

1980

Several observers have suggested that a dysfunction of dynamic balance between platelet aggregation, coagulation and fibrinolysis may be a factor in the pathogenesis of atherosclerosis. This dysfunction, presumably, is correlated with the atherosclerotic vascular lesions, that could reduce the parietal synthesis of heparan-sulphase, prostacyclin and plas minogen activator.

Endothelial modulation of 5-hydroxytryptamine-induced contraction in goat cerebral arteries.

1993

Abstract 1. 1. In isolated goat middle cerebral artery segments, 5-hydroxytryptamine (5-HT, 10 −8 −3 × 10 −5 M) caused concentration-dependent contractions, with EC 50 = 2.1 (1.9−2.5) × 10 −7 M and E max = 60 ± 2% of 50 mM KCl-induced contraction. 2. 2. Mechanical removal of endothelium significantly increased the E max (91 ± 8%) and did not change the EC 50 value of 5-HT-elicited contractions. 3. 3. Incubation of unrubbed arteries with the irreversible inhibitor of EDRF, gossypol (10 −5 M), significantly increased the contractile response to 5-HT ( E max = 77 ± 4%). 4. 4. Incubation of unrubbed arteries with the competitive inhibitor of the NO synthesis, N G -nitro - l -arginine (L-NOARG) …

Progestogens reduce thromboxane production by cultured human endothelial cells.

2011

Objectives Progestogens have been poorly studied concerning their roles in endothelial physiology. Prostanoids are vasoactive compounds, such as thromboxane A2, a potent vasoconstrictor, and prostacyclin, a vasodilator. We examined the effects of two progestogens used clinically, progesterone and medroxyprogesterone acetate, on thromboxane A2 production by cultured human umbilical vein endothelial cells (HUVEC) and investigated the role of progesterone receptors and the enzymes involved in production of thromboxane A2 and prostacyclin. Methods Cells were exposed to 1‐100 nmol/l of either progesterone or medroxyprogesterone acetate, and thromboxane A2 production was measured in culture mediu…

Progestogens stimulate prostacyclin production by human endothelial cells.

2005

BACKGROUND: The effects of progestogens on endothelial physiology are poorly studied. Prostacyclin is a potent vasodilator synthesized by two isoforms of cyclooxygenase (COX) in endothelium. We examined the effects of two clinically used progestogens, progesterone and medroxyprogesterone acetate (MPA), on prostacyclin production by cultured human umbilical vein endothelial cells (HUVEC) and the possible role of progesterone receptors and both COX enzymes. METHODS: Cells were exposed to 1-100 nmol/l of either progesterone or MPA and prostacyclin production was measured in culture medium. RESULTS: Both progestogens significantly increased prostacyclin release in a time- and dose-dependent man…

Platelet sensitivity to prostacyclin and thromboxane production in hyperlipidemic patients

1982

SummaryIn 13 type II hyperlipidemics (10 males and 3 females; mean age 50.2 ± 10.6 years), in 10 type IV hyperlipidemics (7 males and 3 females; mean age 51 ± 13.3 years) and in 23 healthy age-and sex-matched controls, the following parameters were measured: plasma cholesterol; plasma TG; plasma C-HDL; VLDL, separated in a preparative ultracentrifuge; C-LDL; Apo B, with immunoelectrophoretic method; platelet sensitivity to prostacyclin; TXB2 formation in PRP; TXB2 in serum.This study provides evidence for: 1. Reduced platelet sensitivity to prostacyclin, more evident in type II hyperlipidemia that provides an additional mechanism involved in increased platelet aggregation found in type II h…

Thromboxane formation by platelets and platelet sensitivity to prostacyclin in patients with acute myocardial infarction

1981

Safety and tolerability of local treatment with iloprost, a prostacyclin analogue, in patients with Peyronie's disease: a phase I study

2011

Effects of Tolazoline and Prostacyclin on Pulmonary Hypertension in Infants After Cardiac Surgery

1992

Objective To evaluate the hemodynamic effects of tolazoline and prostacyclin in infants with pulmonary vasospasm after cardiac surgery. Design Prospective cohort study. Setting Pediatric ICU. Patients The cohort consisted of 42 infants and children with congenital heart disease and pulmonary hypertension who underwent corrective surgery and were monitored postoperatively using pulmonary artery catheters. Fourteen infants (2 to 12 months old) in this group required postoperative treatment with tolazoline or prostacyclin. Interventions Tolazoline was administered as a bolus of 0.5 mg/kg for treatment of persistent pulmonary hypertension or acute pulmonary hypertensive crisis. If its effective…

Protein tyrosine nitration and thiol oxidation by peroxynitrite-strategies to prevent these oxidative modifications.

2013

The reaction product of nitric oxide and superoxide, peroxynitrite, is a potent biological oxidant. The most important oxidative protein modifications described for peroxynitrite are cysteine-thiol oxidation and tyrosine nitration. We have previously demonstrated that intrinsic heme-thiolate (P450)-dependent enzymatic catalysis increases the nitration of tyrosine 430 in prostacyclin synthase and results in loss of activity which contributes to endothelial dysfunction. We here report the sensitive peroxynitrite-dependent nitration of an over-expressed and partially purified human prostacyclin synthase (3.3 μM) with an EC50 value of 5 μM. Microsomal thiols in these preparations effectively co…