BACKGROUND AND PURPOSE We tested the hypothesis that inhibiting nitric oxide production either before or during transient focal ischemia affects early postischemic brain injury. METHODS Halothane-anesthetized cats underwent 1 hour of left middle cerebral artery occlusion plus 3 hours of reperfusion. Pretreatment groups received either intravenous N omega-nitro-L-arginine methyl ester (L-NAME;...

The effect of different frequencies of direct subtetanic electrical stimulation (14, 20, and 30 Hz) and aminophylline (AMPh) pretreatment on the effect of N(G)-nitro-L-arginine methyl ester (L-NAME) (1 mM) on isolated rat diaphragm was investigated. L-NAME potentiated tension developed (Td) in the diaphragm pretreated with a single concentration of AMPh (1.08 mM) in a frequency-dependent manner...

The roles of nitric oxide (NO) and plasma renin activity (PRA) in the depressor response to chronic administration of Tempol in spontaneously hypertensive rats (SHR) are not clear. The present study was done to determine the effect of 2 wk of Tempol treatment on blood pressure [mean arterial pressure (MAP)], oxidative stress, and PRA in the presence or absence of chronic NO synthase inhibition....

The role of nitric oxide (NO) in microvascular permeability remains unclear because both increases and decreases in permeability by NO synthase (NOS) inhibitors have been reported. We sought to determine whether blood-borne constituents modify venular permeability responses to the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We assessed hydraulic conductivity (L(p)) of pipette-per...

Nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS). NOS can be inhibited by NG-nitro-L-arginine methyl ester (L-NAME); and stimulated by supplementing the diet with L-arginine. The aim of this study was to investigate the influence of NOS activity on the response of rabbits to chronic partial bladder outlet obstruction (PBOO). Surgical PBOOs (2 and 8 weeks) were per...

Aldosterone interacts with mineralocorticoid receptor (MR) to stimulate sodium reabsorption in renal tubules and may also affect the vasculature. Caveolin-1 (cav-1), an anchoring protein in plasmalemmal caveolae, binds steroid receptors and also endothelial nitric oxide synthase, thus limiting its translocation and activation. To test for potential MR/cav-1 interaction in the vasculature, we in...

introduction: the relation between morphine and nitric oxide release has been shown. due to important role of nitric oxide in regulation of skin blood flow, the aim of this study was to investigate the effect of nitric oxide synthase inhibitor (l-name) and nitric oxide synthesis precursor (l-arginine) on skin blood flow of intact and morphine-dependent rats. methods: skin blood flow of hind paw...

Nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS). NOS can be inhibited by NG-nitro-L-arginine methyl ester (L-NAME) and stimulated by supplementing the diet with L-arginine. The aim of this study was to investigate the influence of NOS activity on the response of rabbits to chronic partial bladder outlet obstruction (PBOO). Surgical PBOOs (2 and 8 wk) were perform...

Inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) activates vascular angiotensin-converting enzyme (ACE) and causes oxidative stress. We investigated the role of oxidative stress in the pathogenesis of ACE activation in rats. Studies involved aortas of rats receiving no treatment, L-NAME, L-NAME plus L-arginine, or L-NAME plus an antioxidant drug (N-...

To test the hypothesis that NO influences aldosterone production in humans, we examined the effect of N(G)-nitro-L-arginine methyl ester (L-NAME) on aldosterone concentrations in the presence and absence of the NO precursor L-arginine (3 g TID) and the angiotensin-converting enzyme inhibitor ramipril (10 mg QD). Ten normal subjects were given L-NAME (66 microg/kg per min for 30 minutes) or vehi...