Catecholamine Metabolism in Experimental Hypertension in the Rat

Champlain, Jacques de; Krakoff, Lawrence R.; Axelrod, Julius

doi:10.1161/01.res.20.1.136

Cited by 141 publications

(60 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Serum proteins were precipitated by the addition of 3 ml of 10% trichloroacetic acid per ml of serum and removed by centrifugation at 13,000 X g for 20 min. Proline was measured (10) Ci/ mmol). Starting 24 hr after the injection of label, 1.5-g injections of L-proline in 10 ml of H20 were administered twice daily and continued for 12 days.…”

Section: Methodsmentioning

confidence: 99%

“…Potassium borate buffer with KCI was used in place of the sodium pyrophosphate buffer with NaCl, and alanine was added to increase the sensitivity (13). Extractions were performed with 11 ml of toluene, and 10 ml of the toluene extract was added to a vial containing 10 The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U. S. C. §1734 solely to indicate this fact.…”

Section: Methodsmentioning

confidence: 99%

“…Normotensive rats (12-weeks-old) with an average body weight of 373 g were kept in disposable cages in a hood. DOCA/salt hypertension was produced in uninephrectomized 6-week-ole male Wistar rats by twice weekly subcutaneous injection of DOCA (5 mg per rat) (10,11). Rats were maintained on the standard diet and allowed free access to drinking water containing 1% NaCl.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Increased turnover of arterial collagen in hypertensive rats.

Nissen¹,

Cardinale²,

Udenfriend³

1978

Proc. Natl. Acad. Sci. U.S.A.

174

View full text Add to dashboard Cite

The turnover of total collagen in several tissues of 12-week-old normotensive and hypertensive rats was estimated by using tritium-labeled proline as a precursor. The effect of reutilization of the label was minimized by treatment with large doses of unlabeled proline subsequent to administering the radioactive imino acid. The collagen from skin, tail tendon, aorta, and mesenteric artery in normotensive animals had a half-life of about 60-70 days. In hypertensive animals the half-lives of skin and tail tendon collagen were unchanged but the half-lives of collagen in the aorta and mesenteric artery were reduced to 17 days.In previous studies from this laboratory we reported that hypertension in rats leads to an increased synthesis and deposition of collagen in arteries (1) and microvessels (2). In one set of experiments, treatment of hypertensive rats with f-aminopropionitrile, an inhibitor of collagen crosslinking, resulted in a lowering of the blood pressure within 3 weeks (3). If collagen deposition itself leads to a maintenance of the elevated pressure as we have proposed (3), then this reversal in such a short time may indicate that in hypertension collagen breakdown as well as synthesis may be accelerated. To investigate this possibility, we set about to measure the decay in specific activity of protein-bound hydroxyproline (collagen) after rats were labeled with L-[2,3-3H]proline. Many other investigators have attempted to measure collagen turnover using radioactive amino acids (4-9); however, no correction was made for reutilization of the labeled amino acid that was used. In this report we have utilized an in vivo pulse-chase experiment to minimize the problem of reutilization and have been able to estimate the turnover of collagen in several tissues of normal and hypertensive rats. Normotensive rats (12-weeks-old) with an average body weight of 373 g were kept in disposable cages in a hood. DOCA/salt hypertension was produced in uninephrectomized 6-week-ole male Wistar rats by twice weekly subcutaneous injection of DOCA (5 mg per rat) (10, 11). Rats were maintained on the standard diet and allowed free access to drinking water containing 1% NaCl. After 6 weeks of treatment their average blood pressure was 200 mm Hg (1 mm Hg = 133 Pa) and their average body weight was 416 g. During the experiments, the normotensive animals gained 120 g in 53 days and 250 g in 111 days, while the hypertensives gained 90 g in 53 days. Of the twenty rats started on the DOCA/salt regimen, five died from respiratory infections and three others could not be used because they were also infected. For this reason only three time points could be measured for the hypertensive group. Blood pressure was monitored weekly by the tail cuff microphone method with an instrument made by Hoffmann-La Roche & Co., Basel, Switzerland. MATERIALS AND METHODSBlood was obtained by either cardiac puncture or tail vein bleeding. Serum proteins were precipitated by the addition of 3 ml of 10% trichloroacetic acid per ml of serum and removed ...

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Increased turnover of arterial collagen in hypertensive rats.

Nissen¹,

Cardinale²,

Udenfriend³

1978

Proc. Natl. Acad. Sci. U.S.A.

174

View full text Add to dashboard Cite

show abstract

“…3) of urinary catecholamine metabolites have failed to reveal any consistent abnormalities in cases of essential hypertension. Nonetheless, a few reports of alterations in the metabolism of endogenous or exogenous norepinephrine in human (3)(4)(5)(6) and experimental (7,8) hypertension indicate the issue is not yet settled.…”

Section: Introductionmentioning

confidence: 99%

Catecholamine turnover in normotensive and hypertensive man: effects of antiadrenergic drugs

DeQuattro¹,

Sjoerdsma²

1968

J. Clin. Invest.

View full text Add to dashboard Cite

A B S T R A C T Intravenous administration of tritium-labeled 3,4-dihydroxyphenylalanine (dopa) to human subjects resulted in the labeling of endogenous catecholamines and vanillylmandelic acid (VMA). Determination of the changes in specific activity of these compounds with time in fractional collections of urine and in cardiac biopsies from patients undergoing corrective cardiac surgery permitted estimation of apparent turnover rates. The average half-time of the exponential decline in specific activity of labeled urinary norepinephrine was about 8 hr and that of VMA was 11-16 hr in five normal subjects. No significant differences from normal were observed in eight patients with essential hypertension. The average half-life of norepinephrine was only 5 hr in cardiac patients undergoing surgery, and the levels and rate of decline of cardiac norepinephrine specific activity correlated well with the exponential phase of the urinary disappearance curve. There were significant effects of treatment with alpha-methyltyrosine, reserpine, and pargyline hydrochloride on the labeling and apparent turnover rates of norepinephrine and VMA; the effects noted were consistent with known actions of these three drugs. It is suggested that the technique used is a suitable means of assessing "over-all" catecholamine metabolism in man, particulary if combined with

show abstract

“…Genetic and experimental animal models of hypertension presenting some characteristics to those found in human essential hypertension have been developed (8,24). Central and peripheral sympathetic nerves have been recently demonstrated to play a role in these models (16,17,29,30).…”

Section: Introductionmentioning

confidence: 99%

Circulating and tissue catecholamines in rats with chronic neurogenic hypertension

1986

View full text Add to dashboard Cite

Summary:To study the role of peripheral catecholamines in plasma and different tissues in neurogenic hypertension we measured directly blood pressure, maximum rate of left ventricular pressure rise (dp/dtm~) and heart rate through an aortic catheter 5 weeks after total sino-aortic baroreceptor deafferentation in male Sprague-Dawley rats. Blood samples were collected through the same catheter to determine plasma catecholamine concentrations. Blood pressure and dp/dtmax were significantly higher in neurogenic-hypertensive rats when compared with sham operated rats. Plasma noradrenaline concentrations and plasma adrenaline concentrations reached significantly higher levels in neurogenic-hypertensive rats. In the heart noradrenaline content was lower (when calculated per g wet weight) and in the adrenal medulla adrenaline content was higher in neurogenic-hypertensive rats, when compared with sham operated controls. A significant positive correlation was found between dp/ dtmax and plasma noradrenaline concentrations.It is concluded that sino-aortic baroreceptor deafferentation produces a significant chronic hypertension, probably supported by elevated plasma catecholamine concentrations and enhanced synthesis and release of adrenaline from adrenal medulla.

show abstract

Catecholamine Metabolism in Experimental Hypertension in the Rat

Cited by 141 publications

References 34 publications

Increased turnover of arterial collagen in hypertensive rats.

Increased turnover of arterial collagen in hypertensive rats.

Catecholamine turnover in normotensive and hypertensive man: effects of antiadrenergic drugs

Circulating and tissue catecholamines in rats with chronic neurogenic hypertension

Contact Info

Product

Resources

About