Plasma Catecholamine Levels and Vascular Response in Deoxycorticosterone Acetate Hypertension of Rats

1980 ◽  
Vol 59 (s6) ◽  
pp. 315s-317s ◽  
Author(s):  
W. Rascher ◽  
R. Dietz ◽  
A. Schomig ◽  
J. Weber ◽  
F. Gross
Keyword(s):  
Hind Limb ◽  
Vascular Tone ◽  
Plasma Concentrations ◽  
Plasma Catecholamine ◽  
Vascular Response ◽  
Deoxycorticosterone Acetate ◽  
Pronounced Increase ◽  
Basal Plasma ◽  
Noradrenaline And Adrenaline ◽  
Catecholamine Levels

1. In rats with deoxycorticosterone acetate (DOCA) hypertension basal plasma concentrations of noradrenaline and adrenaline correspond to those of sham-treated controls. 2. In DOCA-treated rats frusemide caused a more pronounced increase in plasma noradrenaline than in control rats. This difference was not observed for adrenaline. 3. In the isolated perfused hind-limb preparation the sensitivity to noradrenaline was already enhanced before blood pressure was elevated. 4. These results suggest that the adrenergic vascular tone is increased in DOCA hypertension in rats.

Plasma Concentrations of Catecholamines in Two Strains of Spontaneously Hypertensive Rats at Different Ages

1981 ◽  
Vol 61 (s7) ◽  
pp. 199s-202s ◽  
Author(s):  
P. Ferrari ◽  
G. B. Picotti ◽  
E. Minotti ◽  
G. P. Bondiolotti ◽  
A. M. Caravaggi ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Plasma Concentrations ◽  
Plasma Catecholamine ◽  
Hypertensive Rats ◽  
Adult Rats ◽  
Plasma Adrenaline ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto ◽  
Normotensive Strain ◽  
Noradrenaline And Adrenaline

1. Blood pressure was measured and plasma levels of noradrenaline and adrenaline were determined radioenzymatically under basal conditions and after 10% blood volume reduction in blood drawn through catheters previously implanted in young and adult rats of two different genetically hypertensive strains: the Kyoto strain (SHR) and the Milan strain (MHS), and in their respective controls: Wistar—Kyoto strain (WKY) and Milan normotensive strain (MNS). 2. Under basal conditions no differences were observed between plasma noradrenaline and adrenaline levels in SHR and MHS rats and in the controls, at any age. Haemorrhage produced a greater fall in the blood pressure (P < 0.01) of young and adult hypertensive strains (SHR-MHS) than in WKY and MNS rats, and a greater rise in plasma adrenaline (P < 0.01). 3. These results suggest that: (a) there may be differences in involvement of the sympathetic nervous system in the pathogenesis of hypertension in SHR and MHS rats but not such as to cause differences in plasma catecholamine levels in either young or adult rats; (b) haemorrhage activates the sympatho—adrenal systems more in SHR and MHS rats, than in controls, and the greater percentage fall in blood pressure is probably due to a difference in reflex venoconstriction.

Plasma and 24 H-Urinary Catecholamine Concentrations in Normal and Patient Populations

1993 ◽  
Vol 30 (1) ◽  
pp. 38-44 ◽  
Author(s):  
G A Ross ◽  
E C Newbould ◽  
J Thomas ◽  
P M G Bouloux ◽  
G M Besser ◽  
...  
Keyword(s):  
Clinical Investigation ◽  
Plasma Catecholamine ◽  
Reference Ranges ◽  
Confidence Limits ◽  
Urinary Catecholamines ◽  
Hospital Patients ◽  
Basal Plasma ◽  
Noradrenaline And Adrenaline ◽  
Positive Results ◽  
Repeat Sampling

Using a single HPLC-ECD methodology, plasma catecholamine data were compiled from 545 patients and 144 healthy subjects, and 24 h urinary free catecholamine data from 106 patients. From these data, normal reference ranges were derived for the clinical investigation of suspected phaeochromocytomas, specifically to address the question as to when a result is normal and when further investigation may be required. We have shown that noradrenaline and adrenaline concentrations in plasma and urine are not normally distributed, and basal plasma noradrenaline is significantly lower in normal volunteers than in hospital patients. We have also demonstrated that a reference range which does not take account of these factors will give a significant number of false-positive results. Age and sex did not appear to be significant variables for either plasma or urinary catecholamines. In the investigation of phaeochromocytoma, 95% confidence limits may be used as a warning to repeat sampling and 99% confidence limits as rendering the diagnosis extremely probable. In patients with phaeochromocytomas, urinary catecholamines had a 99·5% specificity and 100% sensitivity in the diagnosis, and thus provide for a rapid and efficient diagnostic screen.

Effect of respiratory acidosis and alkalosis on plasma catecholamine concentrations in anaesthetized man

1993 ◽  
Vol 84 (1) ◽  
pp. 69-72 ◽  
Author(s):  
J. M. Low ◽  
T. Gin ◽  
T. W. Lee ◽  
K. Fung
Keyword(s):  
Carbon Dioxide ◽  
Plasma Concentration ◽  
Partial Pressure ◽  
Plasma Concentrations ◽  
Respiratory Acidosis ◽  
Gas Mixture ◽  
Plasma Catecholamine ◽  
Arterial Partial Pressure ◽  
Plasma Catecholamine Concentrations ◽  
Noradrenaline And Adrenaline

1. Plasma concentrations of noradrenaline and adrenaline were measured in 11 anaesthetized patients during normocapnia, hypocapnia and hypercapnia. Hypocapnia was produced by deliberate hyperventilation and hypercapnia by adding carbon dioxide to the inspired gas mixture. 2. With a median (range) arterial partial pressure of carbon dioxide of 4.7 (4.2–5.2) kPa, the median (range) plasma concentration of noradrenaline was 0.41 (0.12–0.94) nmol/l and of adrenaline was 0.15 (0.05–0.31) nmol/l. 3. With an arterial partial pressure of carbon dioxide of 2.6 (2.2–3.3) kPa, there was no change in the plasma concentration of noradrenaline [0.37 (0.12–0.86) nmol/l] or that of adrenaline [0.16 (0.05–0.32) nmol/l]. 4. However, with an arterial partial pressure of carbon dioxide of 10.4 (7.6–13.2) kPa, there were significant increases in the plasma concentrations of both noradrenaline [1.13 (0.79–2.05) nmol/l, P < 0.01] and adrenaline [0.67 (0.20–2.92) nmol/l, P < 0.05]. 5. This is the first demonstration in man that respiratory acidosis causes an increase in plasma concentrations of catecholamines.

A comparison of physiological responses to percussive brain trauma in dogs and sheep

1985 ◽  
Vol 62 (4) ◽  
pp. 587-591 ◽  
Author(s):  
J. Eugene Millen ◽  
Frederick L. Glauser ◽  
R. Paul Fairman
Keyword(s):  
Arterial Pressure ◽  
Plasma Concentrations ◽  
Plasma Catecholamines ◽  
Pulmonary Artery Hypertension ◽  
Brain Trauma ◽  
Plasma Catecholamine ◽  
Tissue Water ◽  
Content Type ◽  
Physiological Variables ◽  
Catecholamine Levels

✓ Physiological variables were monitored in dogs and sheep after exposure of the brain to a pressure wave produced by a fluid-percussion device. Mean systemic arterial pressure (SAP), mean pulmonary arterial pressure (PAP), and pulmonary wedge pressure (PWP) were recorded prior to and following trauma. Lung lymph flows (QLYM) were measured prior to and for 2 hours after trauma. Plasma catecholamine levels were quantitated prior to and at 30 seconds following trauma. In 16 dogs, SAP increased from 123 ± 14.6 to 254 ± 60.8 mm Hg (p < 0.0001), PAP increased from 17 ± 4.4 to 27 ± 10.8 mm Hg (p < 0.05), and PWP increased from 4 ± 2.4 to 15 ± 8.8 mm Hg (p < 0.0001), all at 30 seconds posttrauma. All pressures returned to near baseline values within 6 minutes. The QLYM from the right lymph duct in 12 dogs increased from 0.82 ± 0.77 to 2.7 ± 2.1 and 1.88 ± 1.82 ml/30 min, respectively, at 30 and 120 minutes. In five dogs the plasma concentrations of dopamine, epinephrine, and norepinephrine increased from 234 ± 98 to 1906 ± 1384, 609 ± 641 to 19,813 ± 10,234, and 388 ± 194 to 3223 ± 992 pg/ml, respectively (all p < 0.01). In sheep there were no changes in SAP, PAP, PWP, QLYM, or catecholamine levels in response to percussive wave trauma up to 10 atm. Ratios of lung tissue water to dry weight were not significantly different from control animals in either species. The authors conclude that in dogs there is a profound sympathetic discharge resulting in dramatic elevations in plasma catecholamines, systemic and pulmonary artery hypertension, and an increase in pulmonary lymph flow. Sheep fail to demonstrate changes in any of these variables after severe percussive wave brain trauma.

Decreased Platelet-Free Dopamine and Unchanged Noradrenaline and Adrenaline in Essential Hypertension

1988 ◽  
Vol 60 (02) ◽  
pp. 251-254 ◽  
Author(s):  
S E Kjeldsen ◽  
K Gjesdal ◽  
P Leren ◽  
I K Eide
Keyword(s):  
Body Weight ◽  
Essential Hypertension ◽  
Blood Platelets ◽  
Plasma Catecholamine ◽  
Catecholamine Synthesis ◽  
Hypertensive Group ◽  
Plasma Catecholamine Concentrations ◽  
Noradrenaline And Adrenaline ◽  
Over Time ◽  
Normotensive Control

SummaryThe content of free-catecholamines in blood platelets is much higher than in plasma and platelet catecholamines must be taken up from plasma, since platelets lack the enzymes for catecholamine synthesis. There is some evidence that platelet catecholamine content under certain circumstances may be an integrated measure of plasma catecholamine concentrations over time. Platelet-free catecholamines were therefore assayed in 18 untreated patients with essential hypertension and in 16 normotensive control subjects. Mean platelet-free dopamine in the hypertensive group was 3.7 ± 0.4 pg/mg platelet weight, i.e. significantly less than the 6.5 ± 0.9 pg/mg found in the normotensive (p <0.005). Platelet contents of noradrenaline and adrenaline did not differ. Decreased platelet-free dopamine and unchanged platelet noradrenaline and adrenaline persisted after adjustment for increased body weight in the hypertensive group. Although the reasons for decreased platelet-free dopamine in the hypertensive group remain unknown, this finding may add to previous result showing facilitated release of granular contents from blood platelets in patients with essential hypertension. Our data do not support platelet levels of free-catecholamines to be a marker of increased sympathetic tone in essential hypertension.

INFLUENCE OF METYRAPONE ON PLASMA CONCENTRATIONS OF TESTOSTERONE AND ANDROSTENEDIONE IN MAN

1971 ◽  
Vol 68 (3) ◽  
pp. 576-584 ◽  
Author(s):  
K. O. Nilsson ◽  
B. Hökfelt
Keyword(s):  
Body Weight ◽  
Male Patient ◽  
Gradual Increase ◽  
Plasma Concentrations ◽  
Plasma Testosterone ◽  
Testosterone Levels ◽  
Basal Plasma ◽  
Normal Males ◽  
A Minor ◽  
Secondary Hypogonadism

ABSTRACT Metyrapone was administered either orally, 750 mg every four h, in a total of six doses, or intravenously 30 mg per kg body weight as a four h infusion. In three males with normal endocrine functions, metyrapone given orally or intravenously induced a fall in plasma testosterone and an elevation of androstenedione within 2–8 h. When metyrapone was administered to a patient given dexamethasone to suppress endogenous ACTH production, the androstenedione levels did not alter whereas the testosterone levels showed a slight, transient decrease. In two normal females metyrapone administration was followed by a marked increase in plasma androstenedione whereas testosterone showed only a minor, gradual increase. In one male patient with Addison's disease the basal plasma testosterone was normal whereas the level of androstenedione was low. Following metyrapone intravenously, there was a slight suppression of plasma testosterone but no change in the androstenedione concentration. In one patient with primary hypogonadism, two with secondary hypogonadism and two with Klinefelter's syndrome the plasma testosterone was low under basal conditions and did not change following metyrapone. Basal plasma androstenedione was within the range for normal males and increased markedly following metyrapone in all the cases.

Administration of docosahexaenoic acid influences behavior and plasma catecholamine levels at times of psychological stress

Lipids ◽  
1999 ◽  
Vol 34 (S1) ◽  
pp. S33-S37 ◽  
Author(s):  
Tomohito Hamazaki ◽  
Shigeki Sawazaki ◽  
Tetsuro Nagasawa ◽  
Yoko Nagao ◽  
Yuko Kanagawa ◽  
...  
Keyword(s):  
Docosahexaenoic Acid ◽  
Psychological Stress ◽  
Plasma Catecholamine ◽  
Catecholamine Levels

Differential neural regulation of circulating somatostatin-14 and somatostatin-28 in conscious dogs

1993 ◽  
Vol 264 (5) ◽  
pp. G902-G909 ◽  
Author(s):  
G. R. Greenberg
Keyword(s):  
Plasma Concentrations ◽  
Gel Filtration ◽  
Conscious Dogs ◽  
Molecular Forms ◽  
Neural Pathways ◽  
Vagus Nerves ◽  
Solid Meal ◽  
Liquid Meal ◽  
Basal Plasma ◽  
Somatostatin 14

Somatostatin-like immunoreactivity (SLI) released into the circulation after nutrients or secretagogues is heterogeneous. To determine whether similar neural pathways regulate secretion of SLI molecular forms, circulating somatostatin-28 (S-28) and somatostatin-14 (S-14) responses to ingestion of a solid meal, intraduodenal perfusion of a liquid defined formula meal, and intravenous infusion of cholecystokinin octapeptide (CCK-OP, 250 pmol.kg-1.h-1) were measured in four conscious dogs with and without cryogenic blockade of the cervical vagus nerves. SLI was separated by gel-filtration chromatography of extracted, acidified plasma and quantified by radioimmunoassay. Basal plasma concentrations of S-28 were 4.1 +/- 0.6 fmol/ml and of S-14 were 3.8 +/- 0.4 fmol/ml. Ingestion of the solid meal increased plasma SLI threefold, and elevations of S-28 and S-14 were equivalent. After the intraduodenal liquid meal or infusion of CCK-OP, plasma SLI rose twofold, but increments of S-28 exceeded S-14, comprising approximately 70% of SLI released. Vagal blockade by cooling reversibly inhibited both the S-28 and S-14 responses to the solid meal, intraduodenal liquid meal, and CCK-OP. In contrast, atropine (50 micrograms/kg iv), given after solid food, intraduodenal nutrients, and CCK-OP, suppressed S-28 but further increased S-14 responses. Atropine did not, however, alter the suppression of S-14 and S-28 by vagal cooling.(ABSTRACT TRUNCATED AT 250 WORDS)

Sign in / Sign up

Export Citation Format

Share Document