Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Reversal of renal hypertension: Effects on renin, salt and water balance (1978)
    Springer
    Journal of molecular medicine 56 (1978), S. 23-29 
    Details
    ISSN: 1432-1440
    Keywords: Renale Hypertonie ; Entfernung einer Nierenarterienstenose ; Renaler Salz- und Flüssigkeitsverlust ; Renin-Angiotensin System ; Renal hypertension ; Removal of one artery stenosis ; Salt and fluid loss ; Renin-angiotensin system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The effect of removal of one renal artery stenosis on renal sodium and fluid excretion and on the activity of the renin-angiotensin system (RAS) has been investigated in three types of renal hypertension of rats. Blood pressure fell in all experimental models after declamping, independently of changes in urinary sodium and water excretion or plasma angiotensin II (ANG II). Plasma concentrations of ANG II did not rise in response to salt and fluid loss induced by declamping when the contralateral kidney had been removed or when it was depleted from renin. A high renin content of the declamped kidney prevented major salt and fluid loss, whereas renin depletion of this kidney was accompanied by an exaggerated natriuresis and diuresis. Besides this tubular modulation of renal salt and water handling by the local RAS, glomerular filtration rate could be reduced by a stimulated activity of this system in plasma, indicated by a close relationship between serum urea and plasma ANG II levels.
    Notes: Zusammenfassung An drei verschiedenen Modellen des renalen Hochdrucks der Ratte wurde der Einfluß der Entfernung einer Nierenarterienstenose auf die renale Salz- und Wasserausscheidung, die Aktivität des Renin-Angiotensin Systems und die Höhe des Blutdrucks untersucht. Der erhöhte Blutdruck fiel nach Entklammerung in allen Modellen auf Normalwerte ab, unabhängig von den ausgeschiedenen Mengen an Salz und Flüssigkeit und den Änderungen der Plasma Angiotensin II Konzentrationen. Dabei wurden stimulierte Werte für Angiotensin II im Plasma als Folge des Salz- und Flüssigkeitsverlustes nach Entklammerung nur dann beobachtet, wenn die kontralaterale Niere nicht zuvor bereits entfernt oder reninverarmt war. Der plötzliche Anstieg des renalen Perfusionsdruckes nach Entfernung der Stenose führte zu starken Salz- und Flüssigkeitsverlusten, wenn der Reningehalt der betreffenden Niere gering war, während ein hoher Nierenreningehalt mit einer verringerten Elektrolyt- und Wasserausscheidung einherging. Neben dieser tubulären Modulation der renalen Salz- und Wasserausscheidung durch das lokale Nierenrenin-Angiotensin System kann die Stimulation dieses Systems im Plasma über Veränderungen der glomerulären Filtrationsrate die Nierenfunktion beeinflussen. Dies wird deutlich in Situationen, die mit renalem Salz- und Wasserverlust einhergehen; dabei finden sich enge Beziehungen zwischen der Höhe der Plasma-Harnstoff- und der Angiotensin II Werte.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01477449
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Effects ofβ-adrenergic blocking agents on peripheral vascular resistance (1978)
    Springer
    Journal of molecular medicine 56 (1978), S. 87-90 
    Details
    ISSN: 1432-1440
    Keywords: β-Rezeptorenblocker ; peripherer Widerstand ; β 1-Selektivität ; β-adrenergic blocking agents ; Peripheral resistance ; β 1-selectivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The effects of the beta-adrenergic blocking agents propranolol, pindolol, atenolol, bunitrolol, and methypranol on the vascular resistance of isolated perfused hindlimbs of rats were investigated. At concentrations of 0.01 µg/ml in the perfusate dl-propranolol und pindolol significantly increased vascular resistance by blockade ofβ 2-receptor mediated vasodilatation, whereas atenolol, bunitrolol and methypranol had no effect on peripheral resistance at this concentration. With increasing concentrations up to 10 µg/ml all drugs, with the exception of atenolol, caused vasodilatation. We conclude that the specificity of beta-blocking agents can be established in the isolated perfused hindlimb vasculature of rats through its effect on vascular resistance. The lack of inhibition of vascularβ 2-receptors at low concentrations of atenolol and also bunitrolol and methypranol show relative selectivity forβ 1-receptors. The differential effects ofβ-adrenergic agents on vascular resistance may have significance for the clinical use of the drugs.
    Notes: Zusammenfassung Untersucht wurde der Einfluß derβ-Rezeptorenblocker Propranolol, Pindolol, Atenolol, Bunitrolol und Methypranol auf den Gefäßwiderstand der isoliert perfundierten Hinterextremität der Ratte. Bei einer Konzentration von 0,01 µg/ml im Perfusat erhöhten dl-Propranolol und Pindolol den Widerstand deutlich, da die durchβ 2-Rezeptoren vermittelte Vasodilatation ausgeschaltet wurde. Atenolol, Bunitrolol und Methypranol hatten dagegen bei dieser Konzentration keinen Einfluß auf den peripheren Widerstand. Mit steigenden Konzentrationen bis zu 10 µg/ml wirkten alle Pharmaka mit Ausnahme von Atenolol vasodilatatorisch. Wir folgern, daß die Selektivität derβ-Rezeptorenblocker in der isoliert perfundierten Hinterextremität der Ratte durch ihren Effekt auf den Gefäßwiderstand festgestellt werden kann. Wie Atenolol zeigen auch Bunitrolol und Methypranol relative Selektivität fürβ 1-Rezeptoren, da sie in niedrigen Konzentrationen die vaskulärenβ 2-Rezeptoren nicht beeinflussen. Der unterschiedliche Einfluß derβ-Rezeptorenblocker auf den Gefäßwiderstand könnte für die klinische Anwendung der Medikamente Bedeutung haben.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01477458
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Sympathetic nervous activity and the pressor effect of noradrenaline under chronicα-β-adrenoceptor blockade with labetalol in hypertension (1983)
    Springer
    Journal of molecular medicine 61 (1983), S. 661-667 
    Details
    ISSN: 1432-1440
    Keywords: Labetalol ; Essential hypertension ; Plasma noradrenaline ; Noradrenaline infusion ; Plasma renin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In 14 patients with essential hypertension, the influence of theα- andβ-adrenoceptor blocking drug labetalol on blood pressure, heart rate, plasma renin, plasma noradrenaline and pressor effect of exogenous noradrenaline was investigated during long-term treatment. During the initial four weeks of treatment, labetalol at a dose of 400 mg/day showed a slight effect only on supine blood pressure, whereas upright blood pressure was already lowered effectively after the second week of treatment (p〈0.01). An increase in the mean dose to 850 mg/day had an additional blood pressure-lowering effect (p〈0.001), whereby a preferential decrease of the orthostatic blood pressure was no longer apparent. Further increase in the mean dose to 1,000 mg/day at the end of the 12th week did not have an additional blood pressure-lowering effect. Body weight, plasma renin and plasma noradrenaline remained unchanged on labetalol treatment in the lowest and the highest dose. There was, however, an increased pressor effect of exogenous noradrenaline, i.e. anα-adrenoceptor antagonistic effect of labetalol was not detectable under these conditions. The cause of the increased pressor effect was a reduced climination of noradrenaline from plasma, which is probably the consequence of an inhibition of the uptake1 process by labetalol. During long-term treatment with the doses administered, the blood pressure-lowering effect of labetalol appears essentially to be the expression of theβ-adrenoceptor blocking properties of the drug.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01487583
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Sympathetic vascular tone in spontaneous hypertension of rats (1978)
    Springer
    Journal of molecular medicine 56 (1978), S. 131-138 
    Details
    ISSN: 1432-1440
    Keywords: Sympathische Aktivität ; Plasma Noradrenalin ; Adrenalin ; Dopamin ; Gefäßreaktivität ; Uptake Aktivität ; Genetische Hypertonie ; Sympathetic activity ; Plasma noradrenaline ; Adrenaline ; Dopamine ; Vascular reactivity ; Uptake activity ; Spontaneous hypertension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Differences in sympathetic vascular tone between Wistar Kyoto rats (WKR) and stroke prone spontaneously hypertensive rats (spSHR) were determined by comparing the following parameters: sympathetic activity was evaluated by determinations of plasma catecholamines (noradrenaline, adrenaline, dopamine) combined with the measurement of the neuronal and extraneuronal uptake of noradrenaline using an isolated rat heart preparation. The responsiveness of vascular smooth muscle to vasopressor agents was tested in the isolated perfused hindlimb preparation. At the age of 5, 12, 15, and 28 weeks sympathetic nervous activity was significantly higher in spSHR than in WKR since plasma noradrenaline was elevated by almost 50% in the presence of an unaltered activity of the uptake mechanisms. The responsiveness of vascular smooth muscle to noradrenaline was markedly enhanced in spSHR. Besides increased maximal vasoconstriction in response to BaCl2 (20 mmol/l) after potassium chloride depolarization or supramaximal doses of noradrenaline (10−3 mol/l), a supersensitivity of vascular smooth muscle to noradrenaline could also be detected in spSHR (age 5 weeks). The threshold dose and the ED50 were reduced by 25% in spSHR in response to noradrenaline infusions. No changes in threshold or ED50 were found in response to potassium chloride depolarization. The stimulated sympathetic activity in spSHR and the increased responsiveness of resistance vessels to noradrenaline, both contribute to the rise in sympathetic vascular tone. The finding of an increased sympathetic vascular tone in very early stages of hypertension suggest that this factor, producing a primary increase in total peripheral resistance underlies the development of high blood pressure in spSHR.
    Notes: Zusammenfassung Unterschiede des sympathischen Gefäßtonus zwischen spontan hypertonen Ratten (spSHR) und Wistar Kyoto Ratten (WKR) wurden an Hand folgender Größen erfaßt: Die sympathische Aktivität wurde ermittelt durch die Bestimmung der Plasmakatecholamine (Noradrenalin, Adrenalin und Dopamin) bei gleichzeitiger Messung der neuronalen und extraneuronalen Wiederaufnahme von Noradrenalin im isolierten Präparat (Langendorff Herz). Die Ansprechbarkeit glatter Gefäßmuskulatur auf vasopressorische Substanzen wurde in der isoliert perfundierten Hinterextremität der Ratte gemessen. Die sympathische Aktivität war bei spSHR im Alter von 5, 12, 15 und 28 Wochen gesteigert, da die Konzentration von Noradrenalin im Plasma um 50% bei unveränderter neuronaler und extraneuronaler Wiederaufnahme erhöht war. Die Ansprechbarkeit der glatten Gefäßmuskulatur gegenüber Noradrenalin war bei spSHR verstärkt. Neben einer stärkeren maximalen Vasokonstriktion nach supramaximalen Dosen von Noradrenalin (10−3 mol/l) oder BaCl2 (20 mmol/l) fand sich eine spezifische Überempfindlichkeit der einzelnen glatten Muskelzelle gegenüber Noradrenalin bei 5 Wochen alten spontan hypertonen Ratten. Während nach Kaliumdepolarisation keine Unterschiede in der Schwellendosis oder der ED50 auftraten, waren diese bei spSHR für die Noradrenalin-induzierten Widerstandserhöhungen um 25% vermindert. Die stimulierte sympathische Aktivität sowie die erhöhte Ansprechbarkeit der Widerstandsgefäße gegenüber Noradrenalin bei spSHR sind Ursache des gesteigerten sympathischen Gefäßtonus, der über eine Erhöhung des peripheren Widerstandes die Entwicklung des hohen Blutdrucks bei der genetischen Hypertonie der Ratte verursacht.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01477464
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    FLUID AND SALT INTAKE DURING THE DEVELOPMENT OF RENAL HYPERTENSION IN RATS (1980)
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 7 (1980), S. 0 
    Details
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. In Sprague-Dawley rats, two-kidney, one-clip renal hypertension was induced, and the drinking behaviour as well as total fluid and sodium intake were studied before and for 16 days after the operation.2. When water alone was offered as drinking fluid, the blood pressure reached values that were by about 20 mmHg higher than those in the rats which had free choice of drinking water or 2% saline.3. In those rats which had water and 2% saline to drink, the total sodium and fluid intake rose transiently for three days, as compared with that of the sham-operated controls, and increased steeply starting from the 7th and 10th day, respectively. When a tighter stenosis of the renal artery was induced, the pressure rose more rapidly, and the total fluid and sodium intake increased continuously after the operation until the end of the experiment.4. A positive correlation was demonstrable between the height of blood pressure and the total daily intake of fluid and sodium, respectively.5. The relation between the total daily fluid and the total daily sodium intake followed a straight regression line.6. The hypertensive rats which had a high total sodium intake responded to the withdrawal of the 2% saline solution, within 2 days, with increased water intake, decreased food intake, and loss of body weight, whereas the blood pressure remained high.7. In the two-kidney, one-clip hypertension, no ‘critical level of blood pressure’ can be defined, beyond which the contralateral kidney starts to lose sodium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1440-1681.1980.tb00058.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The pharmacological relevance of vital staining with neutral red (1979)
    Springer
    Cellular and molecular life sciences 35 (1979), S. 1475-1476 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The uptake of neutral red into the renin-containing juxtaglomerular granules does not inhibit the release of renin either in basal or in stimulated states of renin secretion. The vasodilating effect of neutral red may be due to a non-specific binding to noradrenaline-receptors in the vascular smooth muscle cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01962793
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Mode of action of sodium nitroprusside on vascular smooth muscle (1975)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 288 (1975), S. 381-402 
    Details
    ISSN: 1432-1912
    Keywords: Vasodilator Drugs ; Antihypertensive Drugs ; Excitation-contraction Coupling ; 45Calcium Uptake ; Cyclic AMP ; Lanthanum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Sodium nitroprusside is a potent relaxant of smooth muscles with a predominantly tonic response, e.g. rat aorta contracted by noradrenaline angiotensin II, Phe2-Lys8-vasopressin, BaCl2, or KCl, and guinea-pig tracheal smooth muscle contracted by carbachol. 2. Smooth muscle preparations from the splanchnic region and with varying degrees of phasic contractility are less sensitive and develop tachyphylaxis (portal vein, duodenum of the rat) or are unresponsive to sodium nitroprusside (vas deferens, uterus of the rat). 3. Cardiac auricles of the guinea pig are not affected by sodium nitroprusside in either frequency or amplitude of spontaneous contractions. 4. Sodium nitroprusside causes a parallel shift of the dose-response curve of rat aorta to noradrenaline to the right and reduces the maximum response. 5. The drug has no blocking or stimulant effect on α-or β-adrenoceptors, respectively. 6. Sodium nitroprusside inhibits the contractile response of calcium-depleted depolarized rat aorta to extra-cellular calcium. Like verapamil, it inhibits the increment in 45calcium uptake of rabbit aorta elicited by K+. Sodium nitroprusside significantly reduces 45calcium binding by microsomes prepared from rabbit aorta. 7. Rabbit aorta was incubated with lanthanum chloride to prevent calcium influx; sodium nitroprusside reduced the maintained rapid contraction phase in response to noradrenaline which is believed to be based on the intracellular activation of calcium. 8. In rat aorta, cellular cAMP and ATP levels were not found to be affected by the drug. 9. Rabbit aorta, “skinned” by glycerination, is unresponsive to sodium nitroprusside. 10. It is concluded that sodium nitroprusside acts on excitation-contraction coupling predominantly in tonic smooth muscle by interfering with both the influx and the intracellular activation of calcium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00501284
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    d-Penicillamine in Wilson's disease presenting as acute liver failure with hemolysis (1982)
    Springer
    Digestive diseases and sciences 27 (1982), S. 1126-1129 
    Details
    ISSN: 1573-2568
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wilson's disease in a young woman presenting with an acute course is described. The clinical manifestations were fulminant hepatic failure associated with marked intravascular hemolysis. Immediated-penicillamine and high-dose steroid therapy did not infuence the course of the disease. Necropsy revealed an increased hepatic copper content and cirrhosis with extensive necrosis of the liver.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01391452
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...