in this study we investigated the effects of endothelium removal and l-name on responses to α-adrenoceptor agonists. male wistar rats were killed by overdose with pentobarbitone sodium, after which the left and right common carotid arteries were removed. rings of arteries 3-4 mm in length were cut from each vessel and then mounted in 10 ml isolated organ bath, bathed in krebs maintained at 37°c...

Plasma adrenaline, noradrenaline, and dopamine concentrations and plasma renin activity were measured in the supine position and after standing for 10 minutes in 14 patients with sustained benign essential hypertension and in five patients with labile hypertension. Results were compared with values obtained in 11 normotensive control subjects. In controls plasma noradrenaline concentrations inc...

The amount of urinary catecholamine of healthy subjects and patients with rheumatoid arthritis, particularly before and after synovectomy, was studied. (1) The urinary catecholamine of patients with rheumatoid arthritis showed a lower value than that of healthy subjects. The greater the amount of intraarticularly injected steroids was and the more severe the stage and class of rheumatoid arthri...

Small-artery responses to vasoconstrictor agonists are important for vascular function. To investigate the signaling pathways involved in contraction, we studied the activation and regulation of p38 mitogen-activated protein kinases (p38MAPKs) and heat shock protein (HSP) kinase by endothelin and noradrenaline in rat mesenteric arteries. Both vasoconstrictors activated p38alpha and/or p38beta b...

1. The rate of noradrenaline-stimulated lipolysis is lower in fat-cells from lactating than from pregnant rats; this difference is eliminated by the addition of adenosine deaminase [Aitchison, Clegg & Vernon (1982) Biochem. J. 202, 243-247]. 2. The activity of 5'-nucleotidase, and hence the capacity of the cells to synthesize adenosine, was the same in fat-cells and also stromal cells of adipos...

BACKGROUND Stress and ethanol are both, independently, important cardiovascular risk factors. OBJECTIVE To evaluate the cardiovascular risk of ethanol consumption and stress exposure, isolated and in association, in male adult rats. METHODS Rats were separated into 4 groups: Control, ethanol (20% in drinking water for 6 weeks), stress (immobilization 1h day/5 days a week for 6 weeks) and st...

1. Adipocytes were isolated from the interscapular brown fat of male rats maintained at 21 degrees C. These animals were controls, streptozotocin-diabetics or 2-day insulin-treated diabetics. 2. With adipocytes from diabetic animals, maximum rates of noradrenaline-stimulated O2 uptake were decreased by 58%, and the Bmax. of [3H]GDP binding to mitochondria was decreased by 55%. Insulin administr...

1. Obesity influences the responsiveness of the microcirculation; constriction is augmented probably reflecting heightened sympathetic nervous activity. 2. The responsiveness of the microcirculation in the forearm to constriction and dilation was therefore examined in 14 men and women with varying degrees of abdominal adiposity, to determine the potential effects of sympathetic nervous activity...

BACKGROUND Generation of reactive oxygen species (ROS) during exercise has been linked to increased oxygen consumption. ROS could also be produced by other mechanisms-for example, a respiratory burst of neutrophils or catecholamine auto-oxidation-when oxygen consumption is only moderately increased. OBJECTIVES To investigate noradrenaline concentrations, neutrophil counts, plasma antioxidants...

BACKGROUND Dinitrosyl nonheme-iron complexes can appear in cells and tissues overproducing nitric oxide. It is believed that due to their chemical nature these species may be implicated in certain pathophysiological events. We studied the possible role of low molecular mass dinitrosyl iron complexes in the control of noradrenaline release in electrically stimulated rat tail artery. RESULTS A ...