Search results for "norepinephrine"
showing 10 items of 234 documents
Age-related regulation of bone formation by the sympathetic cannabinoid CB1 receptor.
2017
The endocannabinoid (eCB) system, including its receptors, ligands, and their metabolizing enzymes, plays an important role in bone physiology. Skeletal cannabinoid type 1 (CB1) receptor signaling transmits retrograde signals that restrain norepinephrine (NE) release, thus transiently stimulating bone formation following an acute challenge, suggesting a feedback circuit between sympathetic nerve terminals and osteoblasts. To assess the effect of chronic in vivo occurrence of this circuit, we characterized the skeletal phenotype of mice with a conditional deletion of the CB1 receptor in adrenergic/noradrenergic cells, including sympathetic nerves. Whereas the deletion of the CB1 receptor did…
Endocrine effects of sauna bath
2020
Abstract Sauna bath brings about numerous acute changes in hormone levels, partly akin to other stressful situations, partly specific for sauna. Norepinephrine increases in those accustomed to sauna bath. Sweating increases the production of antidiuretic hormone, and the renin–angiotensin system becomes activated. Of the anterior pituitary hormones, growth hormone (GH) and prolactin (PRL) secretion is increased. Also β-endorphin has been frequently reported to increase, whereas the responses of antidiuretic hormone and cortisol are variable, probably depending on the type of sauna exposure. Sperm production decreases in particular in sauna-naive men, but reduced fertility has not been assoc…
Neuropeptide Y effects on pineal melatonin synthesis in the rat
1987
Neuropeptide Y (NPY)-like immunoreactivity is present in the rodent pineal gland. To elucidate possible effects on pineal melatonin synthesis NPY (5 nmol/kg body wt.) was injected into the common carotid artery of male rats. Activities of the melatonin biosynthetic enzymes, serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) were determined by means of radioenzymatic methods. Intact light-exposed animal showed increased NAT activity at day- and at nighttime. Blinded animals showed a more than 10-fold reduction of NAT activity after nocturnal NPY injections. HIOMT activity was only slightly influenced at either time. These results are discussed in terms of the p…
The Effect of Tyramine, Noradrenaline, and Angiotensin on the Blood Pressure in Hypertensive Patients with Aldosteronism and Low Plasma Renin
1970
The reactivity to the pressor action of tyramine, noradrenaline, and angiotensin was determined in 9 patients with hypertension, aldosteronism and low plasma renin concentration (4 patients with solitary adrenal adenomas, 3 patients with nodular adrenal hyperplasia, 2 patients with unknown adrenal status). In 7 patients tests were repeated following unilateral or subtotal adrenalectomy respectively. For comparison, 5 patients with phaeochromocytoma, 10 patients with benign essential hypertension, and 12 normotensive control subjects were studied. — In the hypertensive patients with aldosteronism and low plasma renin, responsiveness to tyramine was significantly reduced. In contrast, pressor…
Epinephrine and Norepinephrine Pattern in Elderly Patients with Borderline and Established Hypertension
1989
To evaluate the activity of sympathetic system and of plasm renin in elderly patients with borderline (BH) and established essential hypertension (EH), 31 BH mean age 38 years and 30 EH, mean age 39 years; 15 BH, mean age 66 years, and 15 EH, mean age 68 years, were studied at rest and after dynamic exercise. At the same time blood pressure and heart rate were automatically recorded, while blood samples were collected for PRA and plasma epinephrine (E) and norepinephrine (NE) assays. Plasma E levels showed no significant differences between the groups examined at rest. Nevertheless, young BH had higher plasma E levels than young EH after stress and elderly BH showed plasma E levels higher t…
Metabolic changes induced by combined prolonged exercise and low-calorie intake in man
1984
Thirteen middle-aged women and 10 men walked 344 km during 7 days. The daily walking distances were 57, 53, 67, 53, 41, 36, and 37 km at an average speed of 3.5 km X h-1. During the hike the subjects drank water, mineral drinks, and juices ad libitum. Except for some natural products, no food intake was allowed. During the hike the body weight and serum protein concentration of the subjects decreased by about 7%, on average. Serum triglyceride and total cholesterol decreased drastically, about 30-40% during the hike, but HDL-cholesterol showed a tendency to increase, giving a 40% increment in HDL/total cholesterol ratio. Serum free fatty acids rose 1.5-2 times above the starting level. Seru…
Vasopressor and inotrope treatment for septic shock: An umbrella review of reviews
2021
Abstract Purpose To review the characteristics, findings and quality of systematic reviews (SRs) on the effect of any vasopressor/inotrope on outcomes in adult patients with sepsis compared with either no treatment, another vasopressor or inotrope or fluids. Materials and methods We systematically searched Cochrane Central Register of Controlled Trials, PubMed and Embase (January 1993–March 2021). Descriptive statistics were used. Results Among the 28 SRs identified, mortality was the primary outcome in most (26/28) and mortality was usually (23/28) studied using randomised controlled trials (RCTs). Fifteen SRs focused exclusively on patients with sepsis or septic shock. Sepsis and septic s…
Effect of noradrenaline and isoproterenol on lipopolysaccharide-induced tumor necrosis factor-alpha production in whole blood from patients with chro…
2005
Increased levels of tumor necrosis factor-alpha (TNF-alpha) correlate with poor prognoses in chronic heart failure (CHF). This study demonstrated that noradrenaline and isoproterenol inhibit TNF-alpha production in patients with CHF in ex vivo whole blood in a dose-dependent fashion. The beta-blocker bisoprolol abolishes this effect.
SYMPATHETIC NERVOUS SYSTEM AND BLOOD-PRESSURE CONTROL IN ESSENTIAL HYPERTENSION
1978
Abstract In normotensive subjects an inverse correlation was observed between an index of sympathetic nervous activity (the plasma-noradrenaline concentration during physical exercise) and reactivity to exogenous noradrenaline. This relationship was invariably disturbed in age-matched patients with essential hypertension. Multiple-regression analysis revealed a highly significant correlation between the combination of both factors and the height of mean arterial blood-pressure ( r =0·91). The findings suggest that sympathetic nervous activity and pressor response to noradrenaline together form an important determinant of the arterial blood-pressure level. An inverse relationship could be de…
Evaluation of the clonidine-suppression test in the diagnosis of pheochromocytoma
1988
In this study we examined the preoperative value of the clonidine-suppression test in 15 patients with surgically proved pheochromocytomas. The result of the clonidine-suppression test was pathological (epinephrine plus norepinephrine above 500 ng/l 3 h after clonidine) in 10 of 15 patients (66%). These patients had relatively large tumors and higher basal norepinephrine plasma levels. Out of the 5 cases without a pathological clonidine test 4 had normal basal plasma catecholamine levels with the result that the clonidine test could not be properly applied and 1 case produced a false negative result. These 5 cases generally had smaller tumors and lower plasma catecholamine levels. Two of th…