Buckwalter, John B., Jay S. Naik, Zoran Valic, and Philip S. Clifford. Exercise attenuates a-adrenergic-receptor responsiveness in skeletal muscle vasculature. J Appl Physiol 90: 172–178, 2001.—Attenuation of sympathetic vasoconstriction (sympatholysis) in working muscles during dynamic exercise is controversial. A potential mechanism is a reduction in a-adrenergic-receptor responsiveness. The ...

Chronic (3-day) treatment with prazosin causes an increase in renal alpha 2-adrenergic receptor density and the relocation of renal tubular alpha 2-adrenergic receptors from extrajunctional to postjunctional sites. We investigated whether chronic prazosin treatment (2 mg/kg, i.p.) caused a functional alteration of other renal alpha 2-adrenergic receptors, using the isolated perfused rat kidney....

To determine whether beta-adrenergic agonist therapy increases alveolar liquid clearance during the resolution phase of hydrostatic pulmonary edema, we studied alveolar and lung liquid clearance in two animal models of hydrostatic pulmonary edema. Hydrostatic pulmonary edema was induced in sheep by acutely elevating left atrial pressure to 25 cmH(2)O and instilling 6 ml/kg body wt isotonic 5% a...

Chronic (3-day) treatment with prazosin causes an increase in renal a2-adrenergic receptor density and the relocation of renal tubular a2-adrenergic receptors from extrajunctional to postjunctional sites. We investigated whether chronic prazosin treatment (2 mg/kg, i.p.) caused a functional alteration of other renal a2-adrenergic receptors, using the isolated perfused rat kidney. Prazosin signi...

The hypotensive action of methyldopa has been linked to production of the metabolites methyldopamine and methylnorepinephrine in brain. We have studied the effect of long-term (72 hour) intravenous infusions of methyldopa to awake restrained spontaneously hypertensive rats and normotensive Wistar-Kyoto control animals to look for differences in hypotensive effect, differences in concentrations ...

A case of ventricular tachycardia which reverted with intravenous methoxamine is presented. The methoxamine was used to increase blood pressure during anaesthesia for direct current cardioversion. While alpha adrenergic agonists have been used previously to increase vagal tone via a baroreceptor mechanism to revert supraventricular tachycardias, this is the first case where a sustained ventricu...

The reappearance of beta-adrenergic receptors in C6-glioma cells after desensitization with isoproterenol was studied using the antagonist [3H]CGP-12177. Reappearance had the following properties: (a) it occurred in intact cells only, (b) it was temperature dependent, (c) it required an Na+/H+ gradient, low intracellular Ca2+ activity, and (d) it required ATP, and (e) intact lysosomes. The resu...

To examine whether stimulation of c-adrenergic receptors may affect the oxidative pentose phosphate pathway (PPP) in the rat heart, norepinephrine (NE) and the c-adrenergic agonist norfenephrine were used. NE was administered as a continuous intravenous infusion in awake rats for 3 days. It stimulated the activity of cardiac glucose-6-phosphate dehydrogenase (G-6-PD), the first and regulating e...