Succinic acid monomethyl ester (SAM) was recently proposed as an insulinotropic tool in non-insulin-dependent diabetes mellitus. The present study was designed to define whether SAM has the vascular effect in thoracic aorta of streptozotocin (STZ)-diabetic rats. (1) Body weights of diabetic rats were significantly increased after SAM treatment (P < 0.05). (2) Ten-day SAM treatment did not signi...

SUMMARY Three patients with idiopathic orthostatic (postural) hypotension were infused over a 4-hr period with 104.6 ,uc of 3-hydroxytyramine-2-'4C, the immediate precursor in the synthesis of the sympathetic neurohormone, that is, noradrenaline (norepinephrine). Urine was collected during the infusion period and at various intervals thereafter for a total of 5 days. By means of column fraction...

Nucleus accumbens is proposed as one of the centers in the neural circuitry involved in the regulation of feeding and drinking behaviour in rats. Injection of dopamine and angiotensin-II into this nucleus has been documented to affect water and food intake in rats. Reports on the effect of intracerebral injection of catecholamines on feeding and drinking behaviour in animal models are conflicti...

1. Although plasma noradrenaline and muscle sympathetic nerve traffic have been shown to be suitable markers of sympathetic activity in man, no study has systematically compared the reproducibility and sensitivity of these two indices of adrenergic tone. 2. Reproducibility data were collected in 10 subjects, in whom plasma noradrenaline was assessed by HPLC on blood samples withdrawn from an an...

Endogenous pain control is, in part, mediated by descending inhibition of spinal nociception via spinal release of noradrenaline. Antinociception by activation of descending noradrenergic fibres has partially been attributed to the direct inhibition of nociceptive spinal neurons. Here, we tested the alternative hypothesis: the direct excitation of inhibitory spinal interneurons by noradrenaline...

OBJECTIVE To assess non-invasively the effect of enalapril on cardiac sympathetic neuronal uptake function in patients with congestive heart failure, by using [123I]-metaiodobenzylguanidine (MIBG), which is a noradrenaline analogue. Cardiac MIBG uptake was visualised by single photon emission tomography (SPET). In addition, plasma noradrenaline concentration, indicating systemic sympathetic act...

This study was designed to test the hypothesis of whether activation of presynaptic P2X receptor-gated ion channels elicits noradrenaline release from central catecholaminergic terminals. ATP, alpha,beta-methylene-adenosine 5'-triphosphate (alpha,beta-methyleneATP), and ADP elicited concentration-dependent [3H]noradrenaline outflow from superfused rat hippocampal slices with the following rank ...

The total haemocyte count (THC), phenoloxidase activity, respiratory burst, superoxide dismutase (SOD) activity, phagocytic activity and clearance efficiency in response to pathogen Vibrio alginolyticus were measured when the white shrimp Litopenaeus vannamei (18.4 +/- 1.2 g) were injected individually with noradrenaline at 10(-8), 10(-7) and 10(-6) mol shrimp(-1). For the shrimp that received ...

OBJECTIVE Doxazosin, a selective alpha1-adrenoceptor antagonist, lowers blood pressure by reducing peripheral vascular resistance without causing reflex tachycardia. To discover whether antihypertensive treatment with an alpha1-adrenoceptor blocker is accompanied by an increase in sympathoadrenomedullary activity, we studied plasma catecholamine kinetics before and during treatment with doxazos...