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Volume 2, Number 1, March 2001POPULAR Angiotensin-converting enzyme (ACE) plays a crucial role in the generation of angiotensin II (Ang II) via conversion from angiotensin I (Ang I). There has been substantial recent interest in non-ACE pathways of Ang II generation in the heart, large arteries, and the kidney. In the case of the human kidney, studied when in balance on a low-salt diet, the renal haemodynamic response to Ang II antagonists substantially exceeds the renal response to ACE inhibitors (ACE-I), suggesting that about 30–40% of Ang II-generation occurs via non-ACE pathways. In this study, we examined the relative contribution of non-ACE pathways, by comparing the response to candesartan and to captopril at the top of the dose-response in normal humans when in balance on a low-salt, as well as a high-salt, diet. As anticipated on a low-salt diet, the increase in renal plasma flow (RPF) in response to candesartan (165±14 mL/min/1.73m2) significantly exceeded the response to captopril (118±12 mL/min/1.73m2; p<0.01). In subjects studied on a high-salt diet, the response to candesartan (97±20 mL/min/1.73m2) also significantly exceeded the response to captopril on the same diet (30±15 mL/min/1.73m2; p<0.01). This remarkable response to candesartan in subjects on a high-salt diet, when compared with the response to captopril, suggests that non-ACE-dependent Ang II generation was influenced less than the classical renal pathway with an increase in salt intake, so that the percentage of Ang II generated via the non-ACE pathway rose to the 60–70% range. JRAAS 2001;2:14-18. POPULAR The effects of the specific angiotensin II (Ang II) AT1-receptor blocker valsartan on events related to restenosis were investigated in rabbits after common carotid balloon injury. Six animals were given valsartan from two days prior to injury until 14 days post-injury. Three control groups (n=6 in each group) were either sham-operated, untreated or treated with the angiotensin-converting enzyme (ACE) inhibitor, captopril. Both ACE inhibition and AT1-receptor blockade had marked effects on plasma levels of endothelin ET1, thromboxane TXB2 and 6-keto-PGF1-alpha. The most dramatic effects on ET1 levels were seen in rabbits treated with valsartan, where levels were reduced to values close to those for sham-operated animals (96.85 vs. 86.45 pg/ml). Captopril treatment led to a statistically significant (p<0.01) reduction in ET1 levels compared with untreated animals, but the reduction was only about half that seen with AT1- receptor blockade. TXB2 levels doubled (202.58 vs. 413.28 pg/ml) upon arterial injury in control animals but rose by only 20–35% in rabbits treated with captopril (246.45 pg/ml) or valsartan (268.13). In untreated animals, 6-keto-PGF1-alpha levels decreased slightly after injury, but for both the captopril and valsartan groups, there were significant increases in levels of this prostaglandin derivative, effects attributed to the action of bradykinins. Levels were highest in the captopril-treated animals. Valsartan and captopril treatment led to a significant reduction in neointimal thickness and the extent of lumen stenosis compared with untreated animals. Both treatments were effective in reducing neointimal area and significantly (p<0.05) reduced cell proliferation. The differences between treatments can be attributed to the different actions of the agents, as valsartan leaves the AT2-receptor unblocked, while captopril, through inhibition of Ang II synthesis, prevents stimulation of both receptors. A combination of both treatments may be a possible way forward in the clinical prevention of restenosis. JRAAS 2001;2:19-24. POPULAR Introduction: Marked heterogeneity characterises
blood pressure (BP) responses to antihypertensive drugs. The efficacy of drugs acting
on the renin-angiotensin-aldosterone system (RAAS) is predicted (albeit weakly)
by plasma renin activity (PRA) and it has been assumed that, within
individuals, there would be concordance in efficacy
between drugs acting at different sites to block the RAAS. JRAAS 2001;2:25-30. POPULAR This study compared the cardiovascular and renal effects of long-term telmisartan (3 and 10 mg/kg/day) and lisinopril (10 mg/kg/day) in an animal model combining hypertension and diabetes mellitus. It was a parallel-group study of diabetic, spontaneously hypertensive rats (SHR), treated with control or active treatment for eight months. A non-diabetic SHR control group was run in parallel. Diabetes was induced by streptozotocin (45 mg/kg i.v.) in SHRs aged 9–10 weeks. Animals were treated with telmisartan (3 or 10 mg/kg/day), lisinopril (10 mg/kg/day) or vehicle. Plasma glucose levels, blood pressure (BP), and urinary protein and albumin excretion were measured monthly. Telmisartan treatment significantly reduced BP of diabetic SHRs in a dose-dependent manner (p<0.05, low-dose, n=18; p<0.01, high-dose, n=15). The BP reduction in the lisinopril group was similar to that in the telmisartan 10 mg/kg/day group. Compared with non-diabetic SHRs, untreated diabetic SHRs developed severe proteinuria and albuminuria over the experimental period (p<0.01). In diabetic SHRs, proteinuria and albuminuria were dose-dependently and significantly attenuated by treatment with telmisartan (p<0.01 with the higher dose) and lisinopril (p<0.01). Compared with the untreated diabetic SHRs, cardiac hypertrophy was significantly reduced after treatment with both doses of telmisartan and with lisinopril. Telmisartan, 10 mg/kg/ day, but not lisinopril, significantly attenuated the diabetes-induced increase in glomerular volume. In conclusion, telmisartan, 10 mg/kg/day, is at least as beneficial as lisinopril, 10 mg/kg/day, in lowering BP, reducing cardiac hypertrophy and attenuating renal excretion of protein and albumin in this model. JRAAS 2001;2:31-36. POPULAR Aortic elastin turnover is significantly accelerated in atherosclerosis, partly because of activation of the renin-angiotensin-aldosterone system caused by hypercholesterolaemia. We postulated that angiotensin-converting enzyme inhibitors (ACE-I) prevent the aortic elastin loss in experimental hypercholesterolaemia. Two doses of ACE-I (captopril, enalapril and quinapril) were used: a dose equivalent to that applied to human subjects and a dose 10 times higher. We found that the increase in serum and aortic elastolytic activity in cholesterol-fed rabbits was prevented by high-dose captopril. The elastin content in aorta homogenates from cholesterol-fed rabbits was significantly decreased. The higher dose of captopril, but no other ACE-I, prevented this decrease in aortic elastin content. In cholesterol-fed rabbits the elastin-bound calcium content was significantly elevated. The higher doses of captopril and enalapril lowered the elastin-bound calcium content. In serum and aortic homogenates of cholesterol-fed rabbits, ACE activity was elevated by 15% and 77%, respectively. Both doses of captopril, enalapril and quinapril prevented this cholesterol-induced increase in serum and aortic ACE activity. We conclude that: 1) administration of captopril at doses 10 times higher than those used in humans prevents hypercholesterolaemia increased aortic elastin loss. 2) higher doses of captopril and enalapril prevent the hypercholesterolaemia-induced increase in aortic elastin-bound calcium. JRAAS 2001;2:37-42. POPULAR Angiotensin II (Ang II) is the effector molecule of the renin-angiotensin-aldosterone system (RAAS). This small peptide binds cell surface receptors to maintain a wide variety of haemodynamic responses including salt and water balance, blood pressure and vascular tone. Ang II can also act as a potent growth factor. Under certain conditions however, its growth-promoting effects can be deleterious and lead to vascular disease. The intracellular signalling mechanisms by which the Ang II type 1 (AT1) receptor converts ligand binding to the appropriate cellular response are the focus of this review. Here, the classical signalling pathway utilising heterotrimeric G proteins is discussed. In addition, more recent work examining the role of tyrosine phosphorylation signalling cascades is also examined. Defining the biochemical signalling pathways by which Ang II mediates its physiological effects will advance our understanding of how such a simple molecule elicits such a wide variety of important cellular responses. Furthermore, it may delineate the mechanisms by which Ang II generates a normal vs. an abnormal cellular response, the results of which lead to vascular disease states that are routinely seen in humans. JRAAS 2001;2:4-10. POPULAR Outcome data from randomised controlled trials in hypertensive patients have shown that, in patients aged 65–79 years, there are clear benefits of antihypertensive treatment in those with a sustained systolic blood pressure (SBP) of >160 mmHg, irrespective of diastolic blood pressure (DBP). Although not definitively proven, it is also probable that treating a sustained DBP of >90 mmHg is beneficial. JRAAS 2001;2:11-13. POPULAR The syndrome of hypertension due to a benign aldosterone-secreting adenoma of the zona glomerulosa of the adrenal cortex was first described by Jerome Conn in 1955.1 Since then, a great many case series have been published2-3 and the criteria for the biochemical and histopathological diagnosis have been extensively reported. The tumours are classically canary yellow and rarely more than 1 cm in diameter.4 We report the clinical course of a long-standing hypertensive patient with possibly the largest benign adenoma in the Western medical literature. JRAAS 2001;2:43-44. ABSTRACTOptimal dosing or combination treatments: the example of the renin-angiotensin system inhibition JRAAS 2001;2:48. ABSTRACTGene therapy for hypertension: current status and future perspectives JRAAS 2001;2:48. ABSTRACTSomaitc gene therapy for hypertension with adeno-associated delivery of antisense to angiotensin type 1 receptor mRNA JRAAS 2001;2:48. ABSTRACTPara(auto)crine Ang II is the functionality relevant angiotensin peptide in heart and kidney JRAAS 2001;2:48. ABSTRACTNew roles for aldosterone JRAAS 2001;2:49. ABSTRACTInsights into vascular ACE reactivation despite ACE inhibitor therapy in patients with chronic heart failure JRAAS 2001;2:49. ABSTRACTNon-ACE mediated angiotensin II production JRAAS 2001;2:49. ABSTRACTRelation of primary prevention of stroke with antihypertensive drug-induced effect on angiotensin and sympathetic systems. JRAAS 2001;2:49. ABSTRACTAcute aldosterone administration induces endothelial vasodilator dysfunction in normal man - Evidence for aldosterone-induced vasculiopathy in heart failure? JRAAS 2001;2:50. ABSTRACTEffekt of valsartan and hydrochlorthizide on aortic augmentation pressure index in essential hypertension JRAAS 2001;2:50. POPULAR JRAAS 2001;2:50. POPULAR JRAAS 2001;2:50. POPULAR JRAAS 2001;2:51. ABSTRACTSexual activity and plasma testosterone in hypertensive men treated with valsartan or atenolol. JRAAS 2001;2:51. ABSTRACTCardioprotection induced by Type 1 receptor blockade after ischaemia-reperfusion: Role of angiotensin II Type 2 receptor activation and protein kinase Cε - cGMP signalling JRAAS 2001;2:51. ABSTRACTActivity of the renin-angiotensin system in stenosis and in-stent restenosis in human coronary arteries JRAAS 2001;2:51. ABSTRACTCyclic variation in the angiotensin II receptor expression in the bovine ovary JRAAS 2001;2:52. POPULAR JRAAS 2001;2:52. POPULAR JRAAS 2001;2:52. ABSTRACTChronic AT1 blockade decreases collagen Type 1 synthesis and reverses myocardial fibrosis in hypertensives patients JRAAS 2001;2:52. ABSTRACTAngiotensin II, vascular function and blood pressure JRAAS 2001;2:53. ABSTRACTAngiotensin and atherosclerosis JRAAS 2001;2:53. POPULAR JRAAS 2001;2:53. POPULAR JRAAS 2001;2:53. POPULAR JRAAS 2001;2:54. ABSTRACTTarget organ damage: cardio-renal interactions JRAAS 2001;2:54. POPULAR JRAAS 2001;2:54. ABSTRACTSuccessful BP reduction using sequential angiotensin-blockade and renal arterial angioplasty-stenting for refractory hypertension associated with severe bilateral atheromatous renal arterial stenosis JRAAS 2001;2:54. POPULAR JRAAS 2001;2:55. POPULAR JRAAS 2001;2:58. POPULAR JRAAS 2001;2:58. POPULAR JRAAS 2001;2:58. ABSTRACTThe DIabetic Retinopathy Candesartan Trials (DIRECT) Programme JRAAS 2001;2:58. ABSTRACTCharacterisation of the effects on renal potassium [K] excretion of candesartan an [C] versus lisinopril [L] in hypertensive patients with typw II diabetes Mellitus [DMII] and preserved renal function JRAAS 2001;2:59. POPULAR JRAAS 2001;2:59. ABSTRACTReversal of left ventricular hypertrophy by chronic AT1 Blockade. A role for transforming growth factor -ß1? JRAAS 2001;2:59. POPULAR JRAAS 2001;2:59. ABSTRACTComparison of the antihypertensive effects of a fixed-dose combination of telmisartan and hydrochlorothiazide vs. telmisartan monotherapy in mild-to-moderate hypertension JRAAS 2001;2:60. ABSTRACTEffects of candesartan on left ventricular and arterial structure and function in hypertensive patients JRAAS 2001;2:60. ABSTRACTShort-term changes of serum creatinine level after administration of angiotensin-converting enzyme inhibitors is one of the predictors of long-term prognosis of renal function in patients with renal impairment JRAAS 2001;2:60. ABSTRACTCombination treatment with telmisartan and hydrochlorothiazide in black patients with mild-to-moderate hypertension JRAAS 2001;2:60. ABSTRACTCombined therapy of arrhythmias by angiotensin II antagonist converting enzyme inhibitor. JRAAS 2001;2:61. POPULAR JRAAS 2001;2:61. ABSTRACTOptimal dose of losartan for renoprotection and blood pressure reduction in diabetic nephropathy JRAAS 2001;2:61. ABSTRACTAntihypertensive effect of candesartan and amlodpine assessed by home pressure. JRAAS 2001;2:61. ABSTRACTHypothesis for explaining the opposite links in secondary and primary prevention trials between angiotensin II (AII) synthesis and the blood pressure independent stroke risk JRAAS 2001;2:62. ABSTRACTPreserved autoregulation of glomerular filtration rate during candesartan treatment in hypertensive type 2 diabetic patients without overt nephropathy. JRAAS 2001;2:62. POPULAR JRAAS 2001;2:62. ABSTRACTCandesartan cilexitil in hemodialysis patients JRAAS 2001;2:62. ABSTRACTTissue factor activity and thrombin generation in patients with hypertension and ischaemic heart disease treated with ACE inhibitors JRAAS 2001;2:63. ABSTRACTTelmisartan reverses the potassium loss associated with high doses of hydrochlorothiazide JRAAS 2001;2:63. ABSTRACTPharmacokinetic evidence of lack of interaction between telmisartan and simvasatin JRAAS 2001;2:63. ABSTRACTSexual dysfunction in male hypertensive patients treated with beta receptor blockers or angiotensin II receptor blockers JRAAS 2001;2:63. ABSTRACTAutonomic balance variations during chronic treatment with irbesartan and fosinopril in men JRAAS 2001;2:64. ABSTRACTPolymorphism of angiotensin-converting enzyme and angiotensinogen genes and cardiovascular complications of metabolic variant of essential hypertension JRAAS 2001;2:64. POPULAR JRAAS 2001;2:64. ABSTRACTComparison of the pharmacokinetics of single oral doses of paracetamol when given alone or with telmisartan JRAAS 2001;2:64. ABSTRACTIs A1166C polymorphism of angiotensin II AT1- type receptor a risk factor of left ventricular hypertrophy in essentially hypertensive patients? JRAAS 2001;2:65. ABSTRACTThe responses of blood pressure and proteinuria dissociate during dose-titration with losartan in non-diabetic proteinuria JRAAS 2001;2:65. POPULAR JRAAS 2001;2:65. POPULAR JRAAS 2001;2:65. ABSTRACTThe effect of angiotensin II receptor antogonism on sodium, potassium, urea and creatine concentrations during the menstrual cycle JRAAS 2001;2:66. POPULAR JRAAS 2001;2:66. ABSTRACTSafety and efficacy of long-term exposure to monotherapy or combination therapy with telmisartan JRAAS 2001;2:66. ABSTRACTPulse pressure and metabolics in hypertensives during candesartan JRAAS 2001;2:66. ABSTRACTTreatment with losartan and serum potassium/creatinine in essential hypertensive patients JRAAS 2001;2:67. POPULAR JRAAS 2001;2:67. ABSTRACTInfluence of the losartan on heart rate variability JRAAS 2001;2:67. ABSTRACTLong-term effects of losartan on sympathovagal tone in essential hypertensives JRAAS 2001;2:67. ABSTRACTKallikrein-kinin blood system activity in patients with congestive heart failure under losartan and perindopril therapy JRAAS 2001;2:68. ABSTRACTThe effectiveness of antagonists of angiotensine receptors under acute stress-test condition JRAAS 2001;2:68. ABSTRACTLong-term efficacy of candesartan cilexetil in patients with stable congestive heart failure: haemodynamic, neurohormonal and clinical effects JRAAS 2001;2:68. ABSTRACTLong-term effects of AT1-blocker valsartan on haemodynamics and neuroendocrine parameters in patients with congestive heart failure JRAAS 2001;2:68. POPULAR JRAAS 2001;2:69. ABSTRACTThe gap between the clinical measurements and ambulatory blood pressure means in the TReatment and Ambulatory Blood Pressure (TRAP) study JRAAS 2001;2:69. ABSTRACTThe frequency and duration of white coat effect and the reliability of 27 hour ambulatory blood pressure monitoring in the treatment and ambulatory blood pressures (TRAP) study JRAAS 2001;2:69. POPULAR JRAAS 2001;2:69. ABSTRACTPharmacokinetics and tolerability of single-dose and repeated once-daily telmisartan in elderly subjects JRAAS 2001;2:70. POPULAR JRAAS 2001;2:70. POPULAR JRAAS 2001;2:70. ABSTRACTThe effect of pritor on the fibrinolytic response and lipid profile in essential hypertension JRAAS 2001;2:70. ABSTRACTMorning surge of blood pressure in the elderly is more prominent than younger patients in the treatment and ambulatory blood pressures (TRAP) study JRAAS 2001;2:71. ABSTRACTValsartan further improves efficacy safely in hypertensive patients treated with ACE inhibitors JRAAS 2001;2:71. ABSTRACTStable plasma magnesium status in essential hypertensives under mono-therapy with various angiotensin II antagonist JRAAS 2001;2:71. ABSTRACTAntihypertensive effect and arterial distensibility improvement in hypertensive patients treated with losartan or irbesartan JRAAS 2001;2:71. ABSTRACTClinical implication of angiotensin I - converting enzyme I/D, angiotensinogen M235T, G-6A JRAAS 2001;2:72. POPULAR JRAAS 2001;2:72. POPULAR JRAAS 2001;2:72. ABSTRACTHypertensive patients with diabetes mellitus type II inadequately controlled by angiotensin-converting enzyme inhibitors: is the combination with long-acting calcium channel blockers more effective than with beta-blockers? JRAAS 2001;2:72. POPULAR JRAAS 2001;2:73. ABSTRACTEffects of the treatment with losartan in the microalbuminuria in diabetic patients with high blood pressure JRAAS 2001;2:73. ABSTRACTThe effects of pritor on cerebal circulation values in patients with essential hypertension JRAAS 2001;2:73. POPULAR JRAAS 2001;2:73. POPULAR JRAAS 2001;2:74. ABSTRACTInfluence on systolic blood pressure of long-term therapy by eprosartan in essential hypertensives JRAAS 2001;2:74. ABSTRACTCandesartan and cardiovascular risk in patients with essential hypertension JRAAS 2001;2:74. ABSTRACTLosartan improve exercise performance in patients with moderate and severe mitral insufficiently JRAAS 2001;2:74. ABSTRACTValsartan in the treatment of isoloated systolic hypertension in the elderly. JRAAS 2001;2:75. ABSTRACTLong-term telmisartan treatment and cardiac structure in patients with essential hypertension JRAAS 2001;2:75. POPULAR JRAAS 2001;2:75. POPULAR JRAAS 2001;2:75. ABSTRACTEffects of telmisartan on blood pressure and left ventricular wall thickness in patients with mild hypertension JRAAS 2001;2:76. ABSTRACTTelmisartan is effective and well-tolerated in the clinical setting as monotherapy or add-on therapy in patients with mild-to-moderate hypertension. JRAAS 2001;2:76. ABSTRACTOn top of effect of renin-angiotensin-system inhibition? JRAAS 2001;2:76. ABSTRACTComparative effectiveness of enalapril and losartan at patients with heart failure JRAAS 2001;2:76. POPULAR JRAAS 2001;2:77. ABSTRACTThe role of apexcardiography in diagnostics of heart failure JRAAS 2001;2:77. ABSTRACTStudy of the safety of RAAS long-term complete blockade in type II diabetic patients with MAU and essential hypertension JRAAS 2001;2:77. ABSTRACTAngiotensin II increases expression of macrophage migration inhibitiory factor (MIF) in rat brain neurons JRAAS 2001;2:77. ABSTRACTPrevention of cardiac and kidney lesions (due to potassium restriction) by ACE inhibitors or Ang II receptor antagonists. JRAAS 2001;2:78. ABSTRACTAngiotensin IV decreases acute stroke mortality in the gerbil. JRAAS 2001;2:78. ABSTRACTEffect of in vivo treatment of stroke-prone spontaneoulsy hypertensive rats with losartan on platelet activation. Comparison with valsartan and candersartan. JRAAS 2001;2:78. ABSTRACTIdentifying sources of nitric oxide released by angiotensin II in nucleus tractus solitarii JRAAS 2001;2:78. ABSTRACTValsartan and candesartan can inhibit angiotensin II-induced stimulation of endothelin production by vascular endothelial cells JRAAS 2001;2:79. ABSTRACTInhibitory effect of losartan on basolateral angiotensin II receptor mediated fluid and bicarbonate absorption in the rat proximal tubule JRAAS 2001;2:79. ABSTRACTBinding of non-peptide AT1-receptor antagonists to endogeneous AT1-receptors on human renal artery vascular smooth muscle cells. JRAAS 2001;2:79. ABSTRACTComparative effects of losartan, carvedilol and their combination in preventing left ventricular remodelling after acute myocardial infarction in rats JRAAS 2001;2:79. ABSTRACTLosartan has no acute antiarrhythmic effects in rat hearts JRAAS 2001;2:80. ABSTRACTChronic irbesartan treatment reduces the angiotensin II-induced potentiation of responses to phenylephrine in spontaneously hypertensive rats. JRAAS 2001;2:80. ABSTRACTCardioprotection and angiotensin II type 2 receptor upregulation during angiotensin II type 1 receptor blockade in dog and rat in vivo models of reperfused myocardial infarction JRAAS 2001;2:80. ABSTRACTAngiotensin II-induced stimulation of collagen secretion and production in cardiac fibroblasts is mediated via angiotensin II subtype 1 receptor. JRAAS 2001;2:80. ABSTRACTValsartan-induced cardioprotection involves angiotensin II type 2 receptor upregulation in dog and rat in vivo models of reperfused myocardial infarction JRAAS 2001;2:81. ABSTRACTComparative effects of cilazapril, carvedilol and their combination in prevention left ventricular remodelling after acute myocardial infarction in rats JRAAS 2001;2:81. ABSTRACTAngiotensin II and endothelin I receptor density in mesangial cell cultures following contralateral nephrectomy JRAAS 2001;2:81. ABSTRACTDownregulation of angiotensin II receptors in rat mesenteric arteries after organ culture JRAAS 2001;2:81. ABSTRACTPhenylephrine-mediated responses in irbesartan-treated female spontaneously hypertensive rats JRAAS 2001;2:82. POPULAR JRAAS 2001;2:82. POPULAR JRAAS 2001;2:82. ABSTRACTAntiplatelet action of losartan involves TXA2 receptor antagonism but not TXA2 synthase inhibition JRAAS 2001;2:82. ABSTRACTElectrophysiological study of angiotensin II and BAY 10-6735 on guinea pig ventricular myocytes JRAAS 2001;2:83. ABSTRACTThe inhibitory effect of temisartan on the blood pressure response to angiotensin II challenge JRAAS 2001;2:83. ABSTRACTRole of bradykinin and the AT2-receptors in the cardioprotective effect of telmisartan JRAAS 2001;2:83. ABSTRACTCoated pits disruption antagonises the contractions induced by intracellularly administered angiotensin II in isolated rat aortic smooth muscle JRAAS 2001;2:83. |