The renin-angiotensin system has been implicated in obesity-related hypertension and insulin resistance. We examined whether locally produced components of the renin-angiotensin system in adipose tissue and skeletal muscle play an endocrine role in vivo in humans. Furthermore, the effects of beta-adrenergic stimulation on plasma concentrations and tissue release of renin-angiotensin system comp...

Elderly healthy individuals have a reduced exercise tolerance and a decreased left ventricle inotropic reserve related to increased vascular afterload, arterial-ventricular load mismatching, physical deconditioning and impaired autonomic regulation (the so called "β-adrenergic desensitization"). Adrenergic responsiveness is altered with aging and the age-related changes are limited to the β-adr...

The renin–angiotensin system has been implicated in obesity-related hypertension and insulin resistance. We examined whether locally produced components of the renin–angiotensin system in adipose tissue and skeletal muscle play an endocrine role in vivo in humans. Furthermore, the effects of -adrenergic stimulation on plasma concentrations and tissue release of renin–angiotensin system componen...

The neural crest gives rise to numerous derivatives including adrenergic and cholinergic neurons, supportive cells of the nervous system, and melanocytes. In tissue culture, neural crest cells explanted from both cranial and trunk regions were found to differentiate into adrenergic neuroblasts or into pigmented cells when grown in medium containing 10% chick embryo extract. When the embryo extr...

Existing data in the literature indicate that alpha 2-adrenergic receptor agonists have a profound hypotensive action, that sodium attenuates the affinity of alpha 2-adrenergic receptors for agonists, that the location of these receptors in the central nervous system is mainly at the sites of cardiovascular regulation, and that these sites exert a constant tonic inhibition of sympathetic vasoco...

Heart failure represents the endpoint to many triggering cardiovascular pathologies. However, there are molecular and biochemical features that remain common to the failing heart, despite the varying etiologies. Principal among these is heightened activation of the sympathetic nervous system and associated enhancement of adrenergic signaling pathways via the catecholamines, norepinephrine and e...

The interaction of the renin-angiotensin system and the sympathetic nervous system in patients with congestive heart failure is not well understood. We tested the hypothesis that angiotensinconverting enzyme inhibitors can resensitize the fJ-adrenergic receptor system. Guinea pigs were given captopril, isoproterenol, or both for 2 weeks. At death, cardiac sarcolemmal and light vesicle fractions...

To determine the site and possible mechanism of action of adrenergic agents in regulating intraocular pressure, experiments were undertaken to identify, localize, and characterize beta-adrenergic receptors associated with adenylate cyclase in various ocular tissues involved in secretion and reabsorption of aqueous humor. The ciliary process epithelium was found to be enriched in an adenylate cy...

The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenerg...

Influences of central alpha-2 adrenergic agonists on thyrotropin-releasing hormone (TRH)-stimulated gastric acid secretion were examined in the perfused stomach of anesthetized rats. Clonidine, an alpha-2 adrenergic agonist, given subcutaneously or intracerebroventricularly inhibited the gastric acid secretion stimulated by intracerebroventricular TRH. Intracerebroventricular injection of norep...