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Troncy E - - 1996
Pulmonary hypertension is usually treated with intravenous (i.v.) vasodilators, but their use is limited by systemic effects. In the current study, we compared the effects of inhaled nitric oxide and intravenous nitroglycerine on pulmonary and systemic haemodynamic responses as well as on gas exchange measurements in anaesthetized pigs whose pulmonary ...
Cheifetz I M - - 1996
OBJECTIVE: To test the hypothesis that in a swine model of acute respiratory distress syndrome (ARDS) with permissive hypercapnia, inhaled nitric oxide would improve transpulmonary vascular mechanics and right ventricular workload while not changing intrinsic right ventricular contractility. DESIGN: Prospective, randomized, controlled laboratory trial. SETTING: University research laboratory. SUBJECTS: Eleven ...
Tschudi M R - - 1996
Aging is an important determinant of vascular disease. Endothelium-derived nitric oxide (NO) is protective as a vasodilator and inhibitor of platelet function. This study was designed to directly measure effects of prolonged aging on endotheliai NO release in isolated blood vessels and to delineate differences between the systemic and pulmonary ...
Hao J X - - 1996
We have previously reported that we have observed chronic pain-like response to light mechanical stimuli (allodynia) in rats after severe spinal cord ischemia, which resembles some painful conditions in chronic spinally injured patients and is not relieved by a number of conventional analgesics used for treating chronic neuropathic pain. In ...
Bell D R - - 1996
We tested the hypothesis as to whether elevated arterial pressure in hypertension alters cGMP, or cAMP, mediated vasorelaxation. Relaxation to nitroglycerin and isoproterenol was determined in isolated aortic rings from one-kidney, one clip hypertensive (1K1C), coarctation hypertensive (CH) and normotensive control (C) rats. Thoracic aortas from 1K1C and CH rats, ...
Okabayashi K - - 1996
Morbidity caused by early allograft dysfunction, manifested by a progressive increase in pulmonary vascular resistance and a decrease in oxygenation, remains a serious problem in lung transplantation. Inhalation of nitric oxide, an essential homeostatic molecule, has been shown to have beneficial effects on a variety of acute lung injuries. The ...
Ibla J C - - 1996
OBJECTIVE: To determine if nitric oxide decreases pulmonary vascular resistance in hyperinflation-induced pulmonary hypertension. DESIGN: Isolated-perfused lamb lung model. SETTING: Experimental animal laboratory in a university setting. SUBJECTS: Ten isolated-perfused lamb lungs harvested from subjects with a mean age of 29 days. INTERVENTIONS: After induction of anesthesia, endotracheal intubation, and ...
Lyons C R - - 1996
The short-lived, highly reactive NO radical arises in two ways: 1) a rapidly triggered process well suited for homeostatic fine-tuning of blood pressure and 2) a prolonged high-level production best suited for microbicidal activity. Roles in vascular "leakiness" and leukocyte extravasation are also emerging. Continued investigation may yield new therapies ...
Hechtman H B - - 1996
OBJECTIVE: To test the thesis that agonists and antagonists of nitric oxide, when applied topically to the anal and rectal mucosa, could moderate rectal pressure. BACKGROUND: In vitro studies of muscle strips have suggested that tension of the internal anal sphincter is controlled by nitric oxide. METHODS: Gently restrained, unanesthetized ...
Mathie R T - - 1996
AIMS/METHODS: The modulatory role of nitric oxide in portal vasoconstrictor responses was investigated in the isolated perfused liver of cirrhotic rats (induced by carbon tetrachloride/phenobarbitone; n = 6). Age-matched (n = 5) and phenobarbitone-treated rats (n = 5) served as controls. RESULTS: At a constant flow rate of 5 ml/min ...
Ryan J - - 1996
1. Cirrhosis is often complicated by disturbances in the systemic circulation. We have previously demonstrated decreased vascular responses to vasoconstrictors in forearm resistance arteries in subjects with alcoholic cirrhosis. In the current study we investigate the role of the potent endogenous vasodilator nitric oxide in the peripheral circulation of these ...
Chelly J E - - 1996
BACKGROUND: In vitro, halothane appears to affect the role played by nitric oxide in the regulation of vascular tone and cardiac function. In vivo, the results of the interactions between halothane and the nitric oxide pathway remain controversial. The authors investigated the effects of halothane on the cardiac and regional ...
Preik M - - 1996
OBJECTIVE: To assess the dilatory effectiveness of nitric oxide donors in resistance arteries of patients with arterial hypertension in comparison with that in those of normotensive controls. BACKGROUND: Endothelium-dependent vasodilation has been demonstrated to be impaired in arterial hypertension. Besides disturbances in endothelial nitric oxide production a reduced vasodilatory effectiveness ...
Allman K G - - 1996
Inhaled nitric oxide is a specific pulmonary vasodilator. This study was undertaken to assess the effect on pulmonary arterial pressure of administering 100% oxygen compared with nitric oxide in oxygen. Thirteen mechanically ventilated children undergoing routine cardiac catheterization for the investigation of congenital heart disease were studied. Pulmonary arterial pressures ...
Boolell M - - 1996
Sildenafil (Viagra, UK-92,480) is a novel oral agent under development for the treatment of penile erectile dysfunction. Erection is dependent on nitric oxide and its second messenger, cyclic guanosine monophosphate (cGMP). However, the relative importance of phosphodiesterase (PDE) isozymes is not clear. We have identified both cGMP- and cyclic adenosine ...
Macedo M P - - 1996
We tested the hypothesis that nerve-induced constriction is modulated by nitric oxide only if shear stress is allowed to increase. Shear stress is the effect of moving fluid producing distortion of endothelial cells. Blood flow to the superior mesenteric artery in anesthetized cats was controlled using a perfusion circuit. Shear ...
Losonczy G - - 1996
1. We have used anaesthetized, acutely instrumented non-pregnant (NP) and late pregnant (P) New Zealand white rabbits to examine the possible role of nitric oxide (NO) in the pregnancy-induced fall of vascular tone and arterial pressure. Systemic, renal and pulmonary vascular resistance, as well as plasma concentrations of cyclic GMP ...
Herbertson M J - - 1996
Decreased contractility of myocytes after cytokine exposure can be prevented by nitric oxide synthase inhibition. Whether this is true in an intact animal model of sepsis is unknown. Anesthetized pigs were pretreated with saline or a nitric oxide synthase inhibitor, N omega-nitro-L-arginine, and then treated with saline or endotoxin. We ...
Pagliaro P - - 1996
1. The effect of nitric oxide (NO) inhibition on heart rate was studied in anaesthetized vagotomized dogs. 2. The effect of changes of baroreceptor stimulation was prevented using an arterial pressure reservoir. 3. After NO-inhibitor (Nitro-L-arginine), heart rate decreased by 8% in spite of an unchanged pressure. 4. When upstream ...
van Obbergh L - - 1996
BACKGROUND/AIMS: Although the cardiac output is increased in liver cirrhosis, some degree of cardiac failure could coexist as suggested by human investigations showing cardiac enlargement in cirrhosis and by animal studies describing a limited response to fluid loading in the cirrhotic rat. Endotoxemia induces similar hemodynamic changes during the septic ...
Auler Júnior J O - - 1996
BACKGROUND: The purpose of this study was to assess the hemodynamic effects of low doses of inhaled nitric oxide in patients after orthotopic heart transplantation. METHODS: Two hours after the operation 10 adult patients who were still under anesthetic effects and undergoing mechanical ventilation inhaled, during 60 minutes, a mixture ...
Booke M - - 1996
OBJECTIVES: To investigate the effects of Nomega-mono-methyl-L-arginine (L-NMMA), an inhibitor of nitric oxide synthesis, on hemodynamics, oxygen transport, and regional blood flow in an ovine model of hyperdynamic sepsis and to compare these effects with the responses to norepinephrine. DESIGN: Prospective, nonrandomized, controlled experimental study with repeated measures. SETTING: Investigational ...
Nattero G - - 1996
The role of vascular phenomena taking place during an attack of migraine are poorly understood. The aim of this study was to measure systemic levels of nitric oxide and endothelin-1, two of the most potent vasoactive mediators known, and to assess vasomotor responses through transcranial Doppler ultrasound monitoring in patients ...
Learmont J G - - 1996
OBJECTIVES: Responses to pressure, agonist-induced constriction, endothelium-dependent vasodilators, and shear stress were investigated in resistance-sized mesenteric arteries in vitro from late-pregnant and nonpregnant rats. STUDY DESIGN: Myogenic tone was determined in arteries mounted on a pressure myograph by evaluating the response to incremental increases in luminal pressure in resting arteries ...
Zabel D D - - 1996
The influence of inhibiting the nitric oxide (NO) synthetase on tissue perfusion as indicated by tissue oxygen tensions was determined. Tissue oxygen probes were placed subcutaneously and on serosal and mucosal surfaces of colon of anesthetized adult rats. After a control period, the inhibitor of NO formation, N(G)-nitro-L-arginine methyl ester ...
Rademaker M T - - 1996
1. The role of nitric oxide (NO) in congestive heart failure was investigated by studying the acute haemodynamic, hormonal and renal effects of N(G)-monomethyl-L-arginine (L-NMMA(, a nitric oxide inhibitor, given as incremental bolus doses in six sheep before (normal) and after induction of heart failure (HF) by rapid left ventricular ...
Romero-Alvira D - - 1996
This hypothesis proposes that high blood pressure is a pathological state associated with a loss of the balance between pro-oxidation and antioxidation, energy depletion, and accelerated aging in the target organs, such as heart, kidney and brain. Different nutritional, environmental, pharmacological factors and/or associated pathologies (diabetes, arteriosclerosis, cancer, alcoholism, etc.) ...
Ea-Kim L - - 1996
We examined whether a histamine (H3)-agonist, (R) alpha-methylhistamine, [(R) alpha-MeHA] reduced the pressor responses induced by nicotine in urethane-anesthetized guinea pigs treated by atropine. Nicotine dose-dependently increased the basal mean arterial pressure (MAP) and the heart rate (HR) of the preparation. Both effects were due to stimulation of sympathetic ganglia, ...
Verma S - - 1996
The present study examined the endothelium-dependent and -independent responses of isolated mesenteric arteries to acetylcholine and the endothelium-independent vasodilator sodium nitroprusside in mesenteric arteries from fructose-induced hypertensive rats. Fructose feeding resulted in hyperinsulinemia and elevated blood pressure when compared to controls (plasma insulin, 5.9 +/- 0.4 v control 3.6 +/- ...
Lowson S M - - 1996
We investigated the response to varying concentrations of inhaled nitric oxide (NO) in 18 patients with acute respiratory distress syndrome (ARDS). The study was divided into two parts. In Part 1, 5-40 ppm of inhaled NO was evaluated in 10 patients with ARDS. In Part 2, 0.1-10 ppm of inhaled ...
Seo H G - - 1996
Nitric oxide (NO) is synthesized from L-arginine by three isoforms of NO synthase (NOS). It is essential to suppress the function of the inducible isoform (macNOS) for amelioration of some inflammatory diseases in which the cytotoxic effect of NO is involved. S-Ethylsiothiourea (S-EIU) was reported to be a potent and ...
Soma M - - 1996
Endothelial cells synthesize and release nitric oxide (NO) and prostacyclin (PGI2) which are involved in the regulation of vascular tone and blood pressure. Our objective was to evaluate the effects of inhibiting NO synthesis on vascular prostaglandin (PG) and cyclic nucleotide production, as well as the pressor response to norepinephrine ...
Frank M W - - 1996
OBJECTIVES: We sought to determine whether endothelium-derived relaxing factor (nitric oxide) exerts a tonic vasodilating effect on coronary collateral channels developed in response to myocardial ischemia. BACKGROUND: Although the coronary collateral circulation is known to react to several vasoactive agents, the role of endogenously produced nitric oxide is unclear. METHODS: ...
Unthank J L - - 1996
The role of endothelium-derived nitric oxide (EDNO) in the initial opening and sustained dilation of collateral vessels in the peripheral circulation was investigated. Abrupt arterial occlusion was produced by clamping the rat superficial femoral artery (SFA). Arterial pressures were measured proximal (MAP) and distal (PD) to the occlusion site. In ...
McDougall J J - - 1996
A rôle for nitric oxide in the regulation of knee joint blood flow in the male anaesthetised rat was investigated using laser Doppler perfusion imaging. Intravenous infusion of the nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) at a rate of 0.1 and 1 mg/kg per h caused an ...
Guarasci G R - - 1996
Nitric oxide has been suggested to be an essential mediator of pressure natriuresis. To investigate this hypothesis, the effect of acute or chronic inhibition of nitric oxide synthase on pressure natriuresis and renal interstitial hydrostatic pressure was studied in anesthetized Sprague-Dawley rats with fixed neural and hormonal influences on the ...
Thorup C - - 1996
Nitric oxide (NO) is produced by enzymes called nitric oxide synthases (NOS). At least three different isoforms of NOS have been identified in the kidney. This study examines the effects of selective inhibition of the inducible isoform (iNOS) and the neuronal isoform (bNOS) on the glomerular capillary pressure (PGC), through ...
Roger N - - 1996
Nitric oxide (NO) has been identified as a neurotransmitter of nonadrenergic noncholinergic bronchodilator nerves. To investigate whether inhaled NO exerts a bronchodilator effect in patients with chronic obstructive pulmonary disease (COPD), we measured the resistance of the respiratory system, using the forced oscillation technique, while breathing NO. Eight patients with ...
Kaye A D - - 1996
OBJECTIVE: To test the hypothesis that pulmonary vasodilator responses to pentoxifylline are dependent on the synthesis of nitric oxide from L-arginine and are independent of the release of cyclooxygenase products. DESIGN: Prospective study. SETTING: Research laboratory. SUBJECTS: Isolated lobar lung preparation, using mongrel cats. INTERVENTIONS: In separate experiments, the effects ...
Learmont J G - - 1996
OBJECTIVES: The aim of this study was to determine the dilation that occurs in response to increments of intraluminal flow in isolated human small fetoplacental arteries and to investigate the role played by nitric oxide. STUDY DESIGN: Small fetoplacental arteries (mean luminal diameter 482 +/- 31 micrometers, n = 17, ...
Skimming J W - - 1996
This study was designed to determine indirectly if the changes in ovine fetal pulmonary vascular tone caused by i.v. injections of nitric oxide-containing solutions are mediated by cGMP. We first characterized the dose-response relationship of bolus intrapulmonary injections of zaprinast (a cGMP-selective phosphodiesterase inhibitor) and nitric oxide solutions. Injections of ...
Roberts-Thomson P - - 1996
Blood flow in the renal artery, superior mesenteric artery and infra-renal abdominal aorta of conscious rabbits was measured by Doppler ultrasound. Arterial pressure, heart rate and blood flow responses were assessed following 0.2 and 0.8 nmol/kg intravenous endothelin-1. The effects of the following antagonists on these responses were examined: phentolamine, ...
Grassi-Kassisse D M - - 1996
1. The canine isolated spleen was perfused at constant flow with warmed (37 degrees C) Krebs solution while the splenic arterial perfusion pressure (SAPP) and spleen weight were recorded continuously. An augmented smooth muscle tone was maintained by a continuous intra-arterial infusion of noradrenaline (0.01-0.1 mumol min-1) throughout the experiment. ...
Carmignani M - - 1996
The effects of 1 microgram/mL of vanadium, given for 12 mo as sodium metavanadate in drinking water, on cardiovascular and biochemical indices of male rabbits were investigated. At the end of the exposure period, vanadium was more accumulated in bones and kidneys than in spleen and liver; the cardiac ventricles ...
Baylis C - - 1996
Nitric oxide plays several crucial roles in control of blood pressure and kidney function and in the dietary response to salt in normal humans and animals. Nitric oxide deficiency leads to hypertension and renal damage in experimental animals and may be related to the development of some hypertensive disorders in ...
Cohen A H - - 1996
While it is known that nitric oxide (NO) is an important modulator of tone in the hypertensive pulmonary circulation, the roles of cyclic 3'-5'-guanosine monophosphate (cGMP) and cGMP-phosphodiesterase (PDE) are uncertain. We found that isolated lung perfusate levels of cGMP were over ninefold elevated in hypertensive vs. normotensive control rats. ...
Guan H - - 1996
We investigated the contribution of nitric oxide to the short-term blood pressure reduction caused by interruption of the renin-angiotensin system in angiotensin-dependent hypertension. The blood pressure of rats made hypertensive by coarctation of the aorta between the renal arteries at their origin fell after administration of the angiotensin-converting enzyme inhibitor ...
Hinckley K A - - 1996
The potential for participation of the arginine-nitric oxide system in the aetiology of acute equine laminitis has been assessed. Nitric oxide (NO), produced by the action of NO synthase (NOS) on its substrate l-arginine, relaxes vascular smooth muscle to cause vasodilation. An attenuated normal vasodilatory tone may characterise the pathogenesis ...
Lian T S - - 1996
Desmopressin is a synthetic analog of vasopressin used to promote hemostasis and reduce postoperative blood loss. Recent studies have shown that desmopressin decreases arterial blood pressure in the anesthetized rat and relaxes isolated segments of aorta and pulmonary artery. Responses to a clinical preparation of desmopressin were investigated in the ...
Holécyová A - - 1996
The responsiveness of isolated high-pressure (aorta, renal artery) and low-pressure vessels (pulmonary artery) was compared during systemic hypertension induced by chronic inhibition of nitric oxide synthesis by NG-nitro-L-arginine methyl ester (L-NAME) in rats. L-NAME (40 mg/kg/day) was given to animals in their drinking water. After 4 weeks of L-NAME treatment, ...
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