To study the possible role of catecholamines in platelet activation, platelet aggregation stimulated by AI?P, collagen, arachidonic acid and l-epinephrine, thromboxane B2 (TXB2) formation and plasma levels of catecholamines and renin were studied in healthy men both before and after 6 days of propranolol treatment (40 mg three times daily) under control conditions and during sympathoadrenergic ...

OBJECTIVE The growing evidence from laboratory and clinical studies has shown that the stress hormone, norepinephrine, and chronic stress promote tumor progression in a variety of tumor types. Chemokines and chemokine receptors have been shown to play a pivotal role in tumor progression. Recently, norepinephrine was reported to have a significant effect on macrophage migration by altering the e...

Gender differences in human cardiovascular norepinephrine transporter function may be mediated through female sex hormones. We studied 16 healthy eumenorrheic women (25+/-1 years) during the early follicular phase (day 5+/-0) and midluteal phase (day 22+/-0) of the menstrual cycle. In a randomized, crossover, double-blind fashion, subjects ingested 8 mg of the selective norepinephrine transport...

BACKGROUND Whether or not norepinephrine infusions for support of hemodynamic status in patients with septic shock should be weight based is unknown. This situation is particularly pertinent in patients who are extremely overweight or obese. OBJECTIVE To compare dosing requirements and effect of norepinephrine on blood pressure in obese and nonobese patients with septic shock. METHODS In a ...

Neuropeptide Y is colocalized with norepinephrine in both central and peripheral noradrenergic neurons. In this study, we examined the regulatory mechanisms of neuropeptide Y on norepinephrine release in the medulla oblongata of rats. Neuropeptide Y inhibited the stimulation-evoked [3H]norepinephrine release in a dose-dependent manner in slices of medulla oblongata of Sprague-Dawley rats (1 Hz,...

Hearse, David J., and Fiona J. Sutherland. Catecholamines and preconditioning: studies of contraction and function in isolated rat hearts. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H136–H143, 1999.—The aims of this study were to determine whether 1) like ischemic preconditioning, transient exposure to norepinephrine before ischemia exacerbates contracture during ischemia and 2) protection ...

BACKGROUND In postural tachycardia syndrome (POTS) and repeated neurocardiogenic presyncope (NCS), orthostatic intolerance occurs without persistent sympathetic neurocirculatory failure. Whether these conditions involve abnormal cardiac sympathetic innervation or function has been unclear. METHODS AND RESULTS Patients with POTS or NCS underwent measurements of neurochemical indices of cardiac...

The effects of hypothermia on the sympathetic neuroeffector junction were studied in the isolated perfused cat spleen. The experiments were aimed at determining the temperature dependence both of prejunctional events, i.e., efflux of norepinephrine from the sympathetic nerves in response to electrical stimulation or to indirectly acting sympathomimetic amines like tyramine or phenethylamine, an...

The role of catecholamines was investigated in uninephrectomized SpragueDawley male rats made hypertensive by administration of desoxycorticosterone and a high salt diet. The accumulation of tritiated norepinephrine and the endogenous norepinephrine levels were measured in the various organs. The content of endogenous norepinephrine and the accumulation of H-norepinephrine 1 hour after its inje...

Epinephrine-producing cells are characterized by the presence of phenylethanolamine N-methyltransferase (PNMT), which catalyzes the formation of epinephrine from norepinephrine. We generated a line of transgenic mice carrying a chimeric gene containing human PNMT cDNA fused to the 4-kilobase fragment of the human dopamine beta-hydroxylase (DBH) gene promoter, to switch catecholamine phenotype i...