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...

Cocaine cardiotoxicity is partly due to sympathetic activation of the heart resulting from inhibition of catecholamine uptake at the sympathetic nerve terminal and possible central sympathetic stimulation and/or inhibition. This study evaluated the role of postsynaptic mechanisms in potentiation by cocaine of cardiac adrenergic responses. Cardiovascular responses (arterial and left ventricular ...

–Noradrenaline and adrenergic agonists were tested on pacemaker-like and silent neurons of the rat rostral ventrolateral medulla using intracellular recordings in coronal brainstem slices as well as in punches containing only the rostral ventrolateral medullary region. Noradrenaline (1–100 μM) depolarized or increased the frequency of discharge of all cells tested in a dose-dependent manner. Th...

1. Rats genetically sensitive to salt-induced hypertension showed higher levels of plasma noradrenaline and adrenaline than rats genetically resistant to hypertension. 2. The hypertension-sensitive rats had higher hypothalamic noradrenaline and lower adrenaline than resistant rats. 3. In response to a high salt diet brain-stem noradrenaline increased in sensitive rats and resistant rats exhibit...

OBJECTIVE To measure plasma concentrations of noradrenaline and neuropeptide Y-like immunoreactivity in relation to cardiac function in patients with congestive heart failure. DESIGN Retrospective analysis of plasma noradrenaline concentrations and neuropeptide Y-like immunoreactivity in the arterial and coronary circulations, in patients with a high or low ejection fraction (31.3% (1.3%) or ...

Noradrenaline uptake was studied using heart muscle from 102 patients undergoing cardiac surgery. Slices of right atrium were incubated in Krebs-Henseleit solution containing 1.3 x 10(-7) M 3H-noradrenaline. Uptake was lower in failing heart muscle and was inhibited not only by increasing the noradrenaline concentration in the incubating medium but also by adding the drugs desmethylimipramine, ...

1. Evidence from animal studies indicates that circulating adrenaline may be taken up into sympathetic nerves, facilitating the release of noradrenaline. To test whether adrenaline acts as a co-transmitter in humans we studied eight healthy men (aged 19-23 years) during isometric handgrip before and after an adrenaline infusion (1-3 micrograms/min for > 30 min). Sympathetic activity was assesse...

Sustained effects of SNS (sympathetic nervous system) and HPAA (hypothalamic-pituitary-adrenal axis) hyperactivity on haemostasis have not been investigated. In the present study, we tested for an association of overnight urinary catecholamine and cortisol excretion with morning plasma levels of fibrinogen, PAI-1 (plasminogen activator inhibitor-1) and D-dimer. Participants (639 male industrial...

The release of endogenous noradrenaline and its deaminated metabolite dihydroxyphenylglycol in the myocardium have been studied in the isolated perfused heart of the rat subjected to three models of energy depletion: ischemia, anoxia, and cyanide intoxication. Anoxia and cyanide intoxication were combined with substrate deficiency at constant perfusion flow. All three energy-depleting procedure...