the regulation of dopamine and serotonin synthesis in rat brain striatal synaptosomes has been studied using hplc methods. noradrenaline was shown to markedly inhibit both the synthesis of dopamine and serotonin. the response of the synaptosomes to the concentrations of noradrenaline appeared to be biphasic, a very effective inhibition occurring at low concentrations (1-5 µm) and a relatively i...

The regulation of dopamine and serotonin synthesis in rat brain striatal synaptosomes has been studied using HPLC methods. Noradrenaline was shown to markedly inhibit both the synthesis of dopamine and serotonin. The response of the synaptosomes to the concentrations of noradrenaline appeared to be biphasic, a very effective inhibition occurring at low concentrations (1-5 µm) and a relativ...

microdialysis was used to measure the effect of benzodiazepines (bdzs) on basal levels and on stress-induced increases of 5 -hydroxytryptamine (5 -ht), 5 - hydroxyind oleacetic acid (5 -hiaa) , noradrenaline (na), and dihydroxyphenylacetic acid (dop ac). the stressors used were a 5 min tail pinch or a 10 min period of restraint. a subcutaneous injection of 5 mg/kg diazepam decreased basal level...

In this study, the possible involvement of L-type voltage-operated calcium channels in the vasorelaxant effect of the flavonoid quercetin was investigated, using the isolated aortic rings from normal male rats. Addition of quercetin (0.1 µM-1 mM) caused a significant dose-dependent relaxation of noradrenaline (NA)- and KCl-preconstricted rings and nifedipine attenuated this response, especially...

In this study, the possible involvement of L-type voltage-operated calcium channels in the vasorelaxant effect of the flavonoid quercetin was investigated, using the isolated aortic rings from normal male rats. Addition of quercetin (0.1 µM-1 mM) caused a significant dose-dependent relaxation of noradrenaline (NA)- and KCl-preconstricted rings and nifedipine attenuated this response, especially...

We investigated neuronal uptake of noradrenaline (NA) at the level of larger vessels (thoracic aorta and vena cava left renal artery and left renal vein lateral saphenous artery and lateral saphenous vein and finally central ear artery and marginal ear vein) in a model devised to mimic heart failure. The model presented here is the rabbit coronary ligation model in which myocardial infarcti...

1. Hypertensive patients with normal renal function showed significantly higher plasma urinary noradrenaline than the normotensive controls, and the hypertensive patients with mild to moderate disturbance of renal function showed the same noradrenaline concentration as the controls. 2. Hypertensive patients with severe renal function disturbance showed significantly higher plasma noradrenaline ...

1. The rates of entry of noradrenaline to plasma and of removal of noradrenaline from plasma, and plasma noradrenaline concentration, were determined in normal subjects and in patients with essential hypertension. Neuronal uptake of noradrenaline was assessed from the plasma tritiated noradrenaline disappearance curve, after infusion to steady state. 2. Noradrenaline disappearance was biexponen...

Sodium chloride solution (0.9%) or noradrenaline in doses of 4, 12 and 36 micrograms h-1 kg-1 was infused for five consecutive days, either intrarenally (by a new technique) or intravenously into rats with one kidney removed. Intrarenal infusion of noradrenaline caused hypertension at doses which did not do so when infused intravenously. Intrarenal compared with intravenous infusion of noradren...

1. The influence of age on the rate of spillover of noradrenaline into plasma, clearance of noradrenaline from plasma, and plasma noradrenaline concentration at rest was studied in 34 healthy subjects aged 20--69 years. 2. The plasma concentration of noradrenaline was dependent on age, values being higher in older subjects. 3. This age-dependence of plasma noradrenaline concentration was due pr...