OBJECTIVES This study evaluated the response to prostacyclin dose reduction in patients with primary pulmonary hypertension (PPH) who developed high cardiac outputs. BACKGROUND Patients on prostacyclin require chronic upward dose titration to overcome tolerance to the medication. No upper limit of effective dose has been described. METHODS We studied 12 patients with PPH treated with chroni...

The hypothesis that nitrates evoke prostacyclin production by vascular endothelium has been reevaluated on cultured umbilical vein endothelial cells and in vascular fragments, both obtained from humans. Endothelial cell monolayers (passages 1 and 2) were washed free of culture medium and exposed for 3 to 5 min to buffer or nitroglycerin (NTG), isosorbide dinitrate (ISDN), or isosorbide-5mononit...

BACKGROUND Propofol (2,6-diisopropylphenol) modulates endothelium-dependent relaxation in some arterial preparations. The effect of propofol on endothelium-dependent, prostacyclin-mediated responses in mesenteric resistance arteries has not yet been clarified. METHODS The effect of propofol was examined on acetylcholine-induced membrane potential changes in the presence of N(G)-nitro-L-argini...

Production of prostacyclin by endothelial cells is considered to be important in rendering the vessel wall nonthrombogenic. Cigarette smoking is an important risk factor in the pathogenesis of atherosclerosis. Here we show that the incubation of cultured human endothelial cells with a cigarette smoke condensate impaired the basal prostacyclin release. Also, the enhanced release of prostacyclin ...

Does endotracheal instilled prostacyclin (epoprostenol) improve oxygenation in preterm infants with persistent pulmonary hypertension? Four preterm infants were studied. Prostacyclin (50 ng x kg(-1)) was injected as an endotracheal bolus. In two patients the prostacyclin bolus was repeated and in one patient prostacyclin was administered continuously. Oxygenation was evaluated through the oxyge...

Previous studies showed that prostacyclin inhibited fibrosis. However, both receptors of prostacyclin, prostacyclin receptor (IP) and peroxisome proliferator-activated receptor (PPAR), are abundant in cardiac fibroblasts. Here we investigated which receptor was vital in the anti-fibrosis effect of prostacyclin. In addition, the possible mechanism involved in protective effects of prostacyclin a...

Prostacyclin is the principal product of prostaglandin (PG) endoperoxide (PGH,) metabolism in rabbit mesenteric arteries and veins, as assessed by synthesis of 6-oxo-PGFla. Formation of PGE,, PGD,, PGFfc, and C17-hydroxyacid of PGH, (HHT) were also detected but arose probably from non-enzymic decomposition of PGH,. The effects of prostacyclin (PGI,), 6-oxo-PGFla and PGE, on sympathetic nerre fu...

Prostacyclin is a powerful vasodilator that is released from vascular endothelial cells. Previous studies in our laboratory have indicated that arachidonic acid metabolites from venous endothelium play an important role in the dilation of adjacent arterioles during muscle stimulation. Furthermore, recent studies have suggested that ATP released from red blood cells during hypoxia stimulates dil...