Nitric oxide (NO) has been suggested to play a key role in the pathogenesis of pulmonary hypertension (PH). To determine which mechanism exists to affect NO production, we examined the concentration of endogenous nitric oxide synthase (NOS) inhibitors and their catabolizing enzyme dimethylarginine dimethylaminohydrolase (DDAH) activity and protein expression (DDAH1 and DDAH2) in pulmonary arter...

Our aim was to investigate whether nitric oxide synthase (NOS) isoforms, responsible for the generation of NO, are expressed during the healing of fractures. To localise the sites of expression compared with those in normal bone we made standardised, stabilised, unilateral tibial fractures in male Wistar rats. Immunostaining was used to determine the precise tissue localisation of the different...

Subplate neurons are early-generated neurons that project into the overlying neocortex and are required for the formation of ocular dominance columns. A subset of subplate neurons express nitric oxide synthase (NOS) and produce nitric oxide (NO), a neuronal messenger thought to be involved in adult hippocampal synaptic plasticity and also in the establishment of certain specific connections dur...

OBJECTIVE We examined the effects of aspirin on basal and beta-adrenoceptor (beta-AR)-mediated nitric oxide synthase (NOS) activity in normal platelets. METHODS NOS activity was determined from the conversion of L-[3H]arginine to L-[3H]citrulline, both basally and following beta-AR stimulation, in platelets from healthy human subjects following both short- and long-term aspirin administration...

Nitric oxide (NO) plays important roles in the regulation of renal function and the long-term control of blood pressure. New roles of NO have been proposed recently in diabetes, nephrotoxicity, and pregnancy. NO derived from all 3 NOS isoforms contributes to the overall regulation of kidney function, and recent advances in our understanding of their regulation have been made lately. In this reg...

Excessive nitric oxide (NO) formation plays important roles in the pathogenesis of shock and multiple organ failure in sepsis and acute lung injury (ALI). Evidence from studies in large animal models of shock provide further insight into the role of NO and the varying nitric oxide synthase (NOS) isoforms. Nonselective NOS inhibition in sepsis models reversed sepsis-induced derangements in hemod...

Fig. 8. Electrophoretic patterns of oxyhaemoglobins. All experiments, with the exception of nos. 13-15, in phosphate, pH 8; I, 0*05; 14 V./cm. Nos. 1 and 2 ascending and descending patterns of rabbit HbO2, concentration = 1-35 g./100 ml., after 430 and 435 min. Nos. 3-15 patterns of mixtures 1:1 of hubman and rabbit HbO2. Left, ascending limb; right, descending limb. Nos. 3 and 4 =Exp. 1 ofTabl...

Nitric oxide (NO) generated from neuronal nitric oxide synthase (NOS-1) in intrinsic cardiac ganglia has been implicated in parasympathetic-induced bradycardia. We provide direct evidence that NOS-1 acts in a site-specific manner to promote cardiac vagal neurotransmission and bradycardia. NOS-1 gene transfer to the guinea pig right atrium increased protein expression and NOS-1 immunolocalizatio...

A high-salt (HS) diet and angiotensin II (Ang II) are both associated with the development of hypertension and impaired endothelial function. We hypothesize that alterations in nitric oxide synthase (NOS) activity or subcellular localization of NOS 3 protein may contribute to endothelial dysfunction in salt-dependent hypertension. To test this hypothesis, two models of salt-dependent hypertensi...

Evidence exists that NO plays a role in the vasodilation that occurs during pregnancy. The purpose of the present study was to determine whether the role of NO is associated with an increase in the activity and protein expression of NO synthase (NOS) in the human uterine artery. Uterine arteries were obtained from pregnant patients (P arteries) and nonpregnant patients (NP arteries). NOS activi...