Pheochromocytoma/paraganglioma (PPGL) are neuroendocrine tumors that frequently produce and release catecholamines. Catecholamine excess can manifest in several cardiovascular syndromes, including cardiomyopathy. PPGL-induced cardiomyopathies occur up to 11% of cases most often associated with an adrenal pheochromocytoma (90%) rarely a paraganglioma derived from the sympathetic ganglia (10%). P...

The maintenance of extracellular Na+ and Cl- concentrations in mammals depends, at least in part, on renal function. It has been shown that neural and endocrine mechanisms regulate extracellular fluid volume and transport of electrolytes along nephrons. Studies of sex hormones and renal nerves suggested that sex hormones modulate renal function, although this relationship is not well understood...

BACKGROUND Cigarette smoking plays a major role in cardiovascular diseases. The acute effects of cigarette smoking produce central nervous system-mediated activation of the sympathetic nervous system. The overactive sympathetic nervous system stimulates the secretion of serotonin (5-HT) and catecholamine into blood at supraphysiological levels. The correlation between these pathological conditi...

The effects of phorbol esters, dioctanoylglycerol (DiC8), and micromolar Ca2+ on protein phosphorylation and catecholamine secretion in digitonin-treated chromaffin cells were investigated. [gamma-32P]ATP was used as a substrate for phosphorylation in the permeabilized cells. 12-O-Tetradecanoylphorbol-13-acetate (TPA) enhanced Ca2+-dependent catecholamine secretion from digitonin-permeabilized ...

Experiments were performed to test the hypothesis that exposure of rainbow trout to repetitive hypoxia would result in a decreased capacity of chromaffin cells to secrete catecholamines owing to increased production of nitric oxide (NO), a potent inhibitor of catecholamine secretion. A partial sequence of trout neuronal nitric oxide synthase (nNOS) was cloned and its mRNA was found to be presen...

BACKGROUND Recent hypotheses have suggested the pathophysiological role of catecholamines in the evolution of the Takotsubo syndrome (TTS). The extent of cardiac and circulatory compromise dictates the use of some form of supportive therapy. This study was designed to investigate the clinical outcomes associated with catecholamine use in TTS patients. METHODS Our institutional database consti...

1. Influx and efflux of catecholamine and adenosine triphosphatase activity in storage vesicles from the adrenal medulla were studied with dl-[(14)C]adrenaline in different media. 2. The lowest values for flux and adenosine triphosphatase activity were observed in sucrose media in which an ATP-dependent influx of catecholamine compensated for an efflux of the same magnitude. Efflux in the prese...

Catecholamines were found to activate Na/H exchange in a concentration-dependent manner in primary cultures of vascular smooth muscle cells (VSMC). The potency order was found to be epinephrine greater than norepinephrine greater than isoproterenol. The major pathway for catecholamine effects appeared to be via interaction with an alpha 1 adrenergic receptor. In addition, it was found that alph...

The kinetics of enzymatic O-methylation of catecholamines were studied under conditions like those used in the radioenzymatic assay of plasma catecholamines. Inappropriate Michaelis-Menten kinetics and linear approximations of exponential equations were not used. Mathematical analysis indicated the importance of the ratio of methyl donor (S-adenosylmethionine) to substrate (catecholamine) conce...

Catecholamine neurotransmitters are synthesized by hydroxylation of tyrosine to L-dihydroxyphenylalanine (L-Dopa) by tyrosine hydroxylase (TH). The elimination of TH in both pigmented and albino mice described here, like pigmented TH-null mice reported previously (Kobayashi et al., 1995; Zhou et al., 1995), demonstrates the unequivocal requirement for catecholamines during embryonic development...