Phenylephrine ameliorates cerebral cytotoxic edema and reduces cerebral infarction volume in a rat model of complete unilateral carotid artery occlusion with severe hypotension.

Background: Phenylephrine is a selective alpha(1) adrenergic receptor agonist that increases arterial blood pressure by peripheral vasoconstriction. However, whether phenylephrine improves the outcome of cerebral ischemia in patients with internal carotid artery disease during hemorrhagic shock is unclear.

Methods: (Experiment 1) Twenty-one adult male Sprague-Dawley rats were anesthetized with isoflurane and their lungs mechanically ventilated.

Effect of positive end-expiratory pressure on inflammatory response in oleic acid-induced lung injury and whole-lung lavage-induced lung injury.

Purpose: The present study investigated the effects of positive end-expiratory pressure (PEEP) on the inflammatory response in two different lung injury models: edematous lung induced by oleic acid (OA); and atelectatic lung induced by whole-lung lavage (LAV).

Methods: Japanese white rabbits (n = 28) were allocated to one of the two lung injury (OA or LAV) groups, and each group was treated with intermittent positive pressure ventilation, using zero end-expiratory pressure (ZEEP) or PEEP (1 cm H(2)O above the lower inflection point [LIP]). Thus, the animals were divided into LAV-ZEEP, LAV-PEEP, OA-ZEEP, and OA-PEEP groups.

The evolution of cerebral ischemia in a rat model of complete unilateral carotid artery occlusion with severe hypotension as detected by diffusion-, T2-, and postcontrast T1-weighted magnetic resonance images.

Severe internal carotid artery stenosis or occlusion is considered to be one of the important causes of stroke. The authors created a complete unilateral carotid artery occlusion model in 15 Sprague-Dawley rats, induced severe hypotension for at least 36 minutes by exsanguination with the target mean arterial pressure being equal or less than 35 mmHg, and investigated the temporal and spatial evolution of cerebral ischemia by diffusion-, T2-, and postcontrast T1-weighted magnetic resonance images. Cerebral ischemia was detected in most regions of the right middle cerebral artery territory during exsanguination.

Blockade of nuclear factor-kappaB activation prevents hypodynamic shock and gastric hypoperfusion induced by endotoxin in anesthetized dogs.

Objective: To investigate whether pyrrolidinone derivative (N2733), an inhibitor of nuclear factor (NF)-kappaB activation, improves altered metabolic and hemodynamic changes and organ dysfunctions caused by endotoxic shock.

Design And Setting: Prospective, randomized, animal study in a laboratory at a university hospital.

Subjects: Twenty-three anesthetized male beagle dogs (10-14 kg).

Effects of partial liquid ventilation on lipopolysaccharide-induced inflammatory responses in rats.

To determine whether partial liquid ventilation (PLV) modified lung inflammatory response, we analyzed blood cytokine levels and cytokine mRNA expression in the lungs, using a rat model of endotoxemia. Thirty-six rats were allocated into one of four groups. The first group received conventional gas ventilation (CV group), the second group received 10 ml/kg perflubron intratracheally in combination with mechanical gas ventilation (PLV group), the third group received 20 mg/kg Escherichia coli lipopolyssacharide (LPS) intravenously in combination with mechanical gas ventilation (LPS group), and the fourth group received PLV and LPS (PLV + LPS group).

Atrial natriuretic peptide infusion improves ischemic renal failure after suprarenal abdominal aortic cross-clamping in dogs.

Objective: The suprarenal abdominal aortic cross-clamping during aortic aneurysm repair causes renal dysfunction after surgery. Atrial natriuretic peptide (ANP), a hormone synthesized by the cardiac atria, induces diuresis-natriuresis and increases glomerular filtration rate. Therefore, we tested the hypothesis that prophylactic ANP infusion could limit the development of acute renal failure after aortic cross-clamping.

Relationships of circulating nitrite/nitrate levels to severity and multiple organ dysfunction syndrome in systemic inflammatory response syndrome.

Excessive nitric oxide (NO) production has been implicated to be responsible for the development of septic shock. To determine whether plasma nitrite/nitrate (NOx) levels are related to the severity of systemic inflammatory response syndrome (SIRS) and the degree of multiple organ dysfunction, we studied plasma NOx levels in 70 patients with SIRS consisting of noninfectious SIRS (n = 32), sepsis (n = 23), and septic shock (n = 15). Infection is a microbial phenomenon characterized by an inflammatory response to the presence of microorganism.

An increase in urinary nitrite/nitrate excretion is associated with the hyperdynamic state after cardiovascular surgery.

Objectives: To test the hypotheses (1) that nitric oxide (NO) production is stimulated after cardiovascular surgery and is related to the hyperdynamic state and (2) that NO production is more prominent in patients with cardiopulmonary bypass.

Design: Prospective, clinical study.

Setting: Intensive care unit in a university hospital.

Atrial natriuretic peptide improves pulmonary gas exchange by reducing extravascular lung water in canine model with oleic acid-induced pulmonary edema.

Objective: The purpose of this study was to examine and compare the effects of atrial natriuretic peptide and furosemide on pulmonary gas exchange, hemodynamics, extravascular lung water, and renal function in a dog model of oleic acid-induced pulmonary edema.

Design: Prospective, comparable, experimental study.

Setting: Laboratory at a university hospital.