Recent developments in the characterization of the adrenergic receptors have led to the identification and purification of the binding subunits of the various catecholamine receptors. beta-Adrenergic receptors have been identified in a wide variety of tissues by photoaffinity labeling with the antagonist [125I]p-azidobenzylcrazolol and have been purified to apparent homogeneity from several of ...

The morphology and distribution of the cholinergic and adrenergic nerve fibres were described in the thyroid gland of the domestic hen. The adrenergic structures were visualised with glyoxylic acid and with immunohistochemical staining for tyrosine hydroxylase (TH), the marker for adrenergic nerve structures. Cholinergic structures were visualised using the Karnovsky and Roots method. It was fo...

PAROXYSMAL ventricular tachycardia of the type provoked by exertion or excitement is a rare condition well described by Wilson et al. in 1932.1 The circumstances under which paroxysms occur suggest that sympathetic stimuli are important in producing the arrhythmia. Responses to sympathetic stimuli have been classified by Ahlquist as either a-adrenergic or /3-adrenergic.2 Chronotropic and cardia...

The presence of sex differences in myocardial β-adrenergic responsiveness is controversial, and limited studies have addressed the mechanism underlying these differences. Studies were performed using isolated perfused hearts from male, intact female and ovariectomized female mice to investigate sex differences and the effects of ovarian hormone withdrawal on β-adrenergic receptor function. Fema...

To elucidate the mechanisms responsible for the increase in a,-adrenergic receptors during ischemia in vivo, we developed a procedure for measuring a,-adrenergic receptors in isolated, calcium-tolerant adult canine myocytes. Specific pH]prazosin binding was rapid, saturable, reversible, and demonstrated the expected order of potency and stereospecificity for the a,-adrenergic receptor. Myocytes...

Acute studies have shown that MC3/4-R stimulation increases sympathetic activity, but the role of adrenergic activation in mediating the cardiovascular and renal responses to chronic melanocortin 3- and 4-receptor (MC3/4-R) activation is unknown. The present study tested whether chronic MC3/4-R activation raises blood pressure and whether these changes are attenuated by alpha1+beta-adrenergic b...

Vascular smooth muscle sensitivity to catecholamine-induced contraction is increased after catecholamine depletion by chemical sympathectomy and decreased after exogenous catecholamine administration. To investigate the role of the vascular o-adrenergic receptor in these alterations, we used the a-1 selective radioligand, (H)-WB-4101, [phenoxy-3-H(JV)]-(2-(2,6-dimethoxyphenoxyethyl)aminomethyl-...

The potential role of adrenergic systems in regulating Na(+) uptake in zebrafish (Danio rerio) larvae was investigated. Treatment with isoproterenol (a generic β-adrenergic receptor agonist) stimulated Na(+) uptake, whereas treatment with phenylephrine (an α(1)-adrenergic receptor agonist) as well as clonidine (an α(2)-adrenergic receptor agonist) significantly reduced Na(+) uptake, suggesting ...

The involvement of prostaglandins synthesized by constitutive (COX-1) and inducible cyclooxygenase (COX-2) in central stimulation of the hypothalamic-pituitary-adrenal (HPA) axis by adrenergic receptor agonists was investigated in conscious rats. COX-1 and COX-2 inhibitor, piroxicam (0.02 and 0.2 microg) and compound NS-398 (0.01 and 0.1 microg), respectively, were given intracerebroventricular...

Adrenergic urticaria, a rare but distinct subtype of the physical urticarias, is characterized by wheals that are typically surrounded by a white halo of vasoconstriction, and by a positive response to intradermal adrenaline and noradrenaline injections. The pathogenesis of adrenergic urticaria is unknown. We report here a case of a 64-year-old woman with adrenergic urticaria who was found to h...