INTRODUCTION In paediatric clinical practice, tests for urinary catecholamines and their metabolites are most often requested to aid in the diagnosis and follow-up of patients with neural crest tumours, particularly neuroblastomas. Neuroblastoma is the most common extracranial solid tumour in children. Each year 80–90 new patients are diagnosed in the UK, most of them infants or toddlers. Neuro...

Bovine adrenal medullary chromaffin cells were used to study the relationship between opioid peptide and catecholamine secretion from the adrenal medulla. Stimulation of chromaffin cells by acetylcholine, nicotine, veratridine, barium, or Ionomycin produced secretion of opioid peptides and catecholamines which was proportional to the cellular content of these substances. Nicotine-evoked secreti...

Based on the in vitro blockade of adrenal catecholamines release by sulfonylurea, we searched for an anti-stress activity of this drug. Stress-induced hyperglycemia and insulin inhibition were employed as adrenergic stress indicators. A standard dose of the oral sulfonylurea glipizide (200 micrograms/100 g), administered 15 min before a 1-h restraint stress to intact or 80% pancreatectomized ra...

BACKGROUND Pheochromocytomas are rare tumors derived from the chromaffin cells of the adrenal medulla. Although these tumors have long been postulated to induce hypertension and cardiomyopathy through the hypersecretion of catecholamines, catecholamines alone may not fully explain the profound myocardial remodeling induced by these tumors. We sought to determine whether changes in myocardial fu...

Broken Heart Syndrome (BHS) is the weakness of heart muscle due to emotional stress or physical called cardiomyopathy. The main etiology a sudden release hormones (catecholamines), such as norepinephrine, epinephrine, and dopamine. About 90% BHS patients are female with average age 67-70"‰ years, most them post-menopausal females. widely supported pathological theories catecholamine-induced car...

• Current uncertainty concerning the action of catecholamines on smooth muscle of coronary arterial vessels is convincingly documented by extensive controversial reports in the literature. Most authors now agree that dilatation is the final result of the action of these agents in vivo," as well as in the isolated perfused heart." Decrease of coronary flow, however, has been observed under many ...

The effect of advanced age on the response of active tension, maximal rate of tension development (dT/dt), and contraction duration to catecholamines and to calcium was evaluated in isometric trabeculae carneae from young adult (6-month-old), middle-aged (12-month-old), and aged (25-month-old) rats. Control values were not age dependent except for that for contraction duration which was prolong...

For various reasons plasma catecholamines should be measured in arterial blood when comparing hypertensive and normotensive groups (1, 2). Measurements of plasma catecholamines in peripheral venous blood may conceal important hypertensive-normotensive differences (2). Plasma catecholamines seem to be subjected to a peripheral arterialvenous fractional extraction of approximately 50%. Thus, arte...

Aggregated platelets and occlusive platelet thrombi were found in small myocardial vessels of dogs on electron-microscope examination after prolonged infusion of norepinephrine. The etiology of the myocardial necrosis and fibrosis induced by catecholamines in experimental animals and seen in patients with pheochromocytoma and patients after norepinephrine treatment for shock may be related to t...

High levels of circulating catecholamines are found in the fetus, and fetal stress and birth induce a marked surge in catecholamine secretion. Little is known about the role of catecholamines on the fetal pulmonary circulation. To determine the effects of catecholamines on the pulmonary vascular tone, we tested the hemodynamic response to norepinephrine and dopamine infusion in chronically prep...