Rationale for a New Low-Dose Triple Single Pill Combination for the Treatment of Hypertension

Two recent large trials showed the potential of single pill combinations (SPCs) with ≥3 low-dose components among people with hypertension who were untreated or receiving monotherapy. In both trials, these 'hypertension polypills' were superior to usual care, achieving >80% BP control without increasing withdrawal due to side effects. However, there are no such products available for prescribers. To address this unmet need, George Medicines developed GMRx2 with telmisartan/amlodipine/indapamide in three strengths (mg): 10/1.25/0.625, 20/2.5/1.25; 40/5/2.5. Two pivotal trials are ongoing to support FDA submission for the treatment of hypertension, including initial treatment. These assess efficacy and safety of GMRx2 compared to: placebo, and each of the three possible dual combinations. Regulatory submissions are planned for 2024, with the aim of providing access to GMRx2 in developed and developing regions. Wider implementation of GMRx2-based treatment strategies will be guided by further research to inform access and appropriate scale up.

Vascular legacy beyond blood pressure control: benefits of perindopril/indapamide combination in hypertensive patients with diabetes

OBJECTIVES

Much of the chronic care of patients with type 2 diabetes mellitus and hypertension involves the prevention of diabetic complications. Renin-angiotensin system inhibitors are recommended as first-line therapies because of their nephroprotective properties. Their combination with metabolically neutral diuretics is recommended to reduce blood pressure, morbidity and mortality. Our objective was to review the mechanisms by which the combination of the angiotensin-converting enzyme inhibitor, perindopril, and metabolically neutral thiazide-like diuretic, indapamide, targets the pathways involved in microvascular and macrovascular diabetic complications.

METHODS

For this narrative review, extensive literature searches were performed using PubMed/Medline. Articles published in English describing clinical trials and mechanism of action studies that were relevant to the treatment of patients with perindopril and/or indapamide were included.

RESULTS

Perindopril/indapamide treatment has been shown to reduce blood pressure and to have significant beneficial effects on arterial distensibility, kidney structure and function, and endothelial function. Recent data also suggests that perindopril may reduce the deleterious accumulation of advanced glycation end products in diabetic tissue. In the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation diabetes trial, perindopril/indapamide treatment significantly reduced the relative risk of microvascular and macrovascular events by 9%, cardiovascular mortality by 18%, and all-cause mortality by 14%. Interestingly, 6 years after the end of the double-blind period, follow-up data showed that the beneficial effects on mortality continued to be significant even though differences in blood pressure and glycated hemoglobin levels had not been significant for several years. Together this data suggests that treatment with perindopril/indapamide has microvascular and macrovascular effects that extend beyond blood pressure lowering and that this treatment might confer a long-lasting beneficial vascular legacy.

CONCLUSION

Moving forward, understanding the pathophysiological bases of the effects that extend beyond those of blood pressure control will help us differentiate between anti-hypertensive choices.

Effects of antihypertensive treatment on plasma apelin, resistin, and visfatin concentrations

INTRODUCTION Adipose tissue has been recently recognized as an endocrine organ secreting a number of adipokines contributing to the development of atherosclerosis, hypertension, chronic kidney disease, endothelial dysfunction, insulin resistance, and vascular remodeling. OBJECTIVES The aim of this study was to determine whether treatment with a β-blocker, calcium antagonist, thiazide-like diuretic, or angiotensin II receptor type 1 influences plasma concentrations of apelin, resistin, and visfatin in obese hypertensive patients. PATIENTS AND METHODS The study included 84 obese patients with essential hypertension. One control group included obese subjects without hypertension, and the other, lean subjects without hypertension. Patients with hypertension were randomized into 4 groups treated for 6 weeks with bisoprolol, amlodipine, indapamide, or candesartan, respectively. RESULTS Mean daily plasma apelin concentrations in patients treated with amlodipine was significantly higher than the baseline values, whereas the difference in plasma apelin concentrations in other treatment groups was not significant. Mean daily plasma resistin concentrations were significantly lower after 6-week treatment with amlodipine, bisoprolol, or indapamide compared with the baseline values. In patients treated with candesartan, no significant differences in resistin concentrations were shown. After 6-week treatment with bisoprolol, mean daily plasma concentrations of visfatin were significantly lower compared with the baseline values. Treatment with amlodipine, candesartan, or indapamide did not significantly affect plasma visfatin levels. CONCLUSIONS Antihypertensive treatment exerts significant and varied effects on adipokine secretion in obese hypertensive patients. Changes in apelin secretion, caused by the use of different antihypertensive drugs, may protect the cardiovascular system and kidneys. The involvement of adipokins in the mechanism of diverse protective effects of antihypertensive drugs, independently of the effect on blood pressure, requires further research.

[STRUCTURAL AND FUNCTIONAL CHANGES MYOCARDIUM HYPERTENSIVE RATS IN APPLYING INDAPAMIDE AND ELLAGIC ACID]

The article investigates the effectiveness of antihypertensive properties of indapamide and ellagic acid in hypertensive rats. As a result of experimental studies determined the effect of drugs on blood pressure and structural recovery of the myocardium of hypertensive rats. Indapamid with ellagic acid reduces the degradation of contractile myofibrils, mitochondria lysis and swelling of the cytoplasm of cardiomyocytes. The study drug is a normalizing effect on the se parameters. The combined use of indapamid and ellagic acid enhances the structural and functional recovery of myocardium energy metabolism normalizes organelles.

Perindopril/indapamide combination in the first-line treatment of hypertension and end-organ protection

This article examines evidence-based findings in the literature on the efficacy of perindopril 2 mg/indapamide 0.625 mg, a first-line, low-dose antihypertensive drug combination. In regulatory Phase II and III trials, perindopril/indapamide significantly lowered blood pressure compared with other first-line therapies (atenolol, losartan and irbesartan). This was also the case in STRAtegies of Treatment in Hypertension: Evaluation, a postregistration study versus current monotherapies and stepped-care therapy with different classes of antihypertensive agents. The efficacy/safety ratio (both clinical and with regard to laboratory parameters) of perindopril/indapamide was good. Perindopril/indapamide provides additional antihypertensive efficacy compared with each component used alone and with current monotherapies, with major efficacy on systolic blood pressure, an important predictor of cardiovascular risk. It also reduces pulse pressure, an independent cardiovascular risk factor, large-vessel arterial stiffness and microcirculatory alterations. The fixed dosage of a once-daily tablet, ensures optimal ease of use and enhances patient compliance. Perindopril/indapamide also reduces target organ damage in patients at high cardiovascular risk, such as patients with cardiac hypertrophy and Type 2 diabetics with albuminuria. These benefits, together with the good efficacy/tolerability ratio, fulfill the requirements of the European Society of Hypertension and of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines for low-dose, first-line combination therapy in hypertension.

[Optimization of pharmacotherapy in patients with essential hypertension with neurohumoral modulators with consideration of data on heart rate variability]

Long-term treatment of patients with essential hypertension (EH) and autonomic dysfunction (sympathicotonia type) with lisinopril in combination with indapamide augmented activity of humoral systems and improved heart rate variability. Addition of a selective beta-blocker bisoprolol to lisinopril/indapamide combination promoted normalization of humoral activity. This gives reason to apply tiered RAAS blockade in order to ensure more effective control of activity of neurohumoral systems in patients with EH ant initial sympathicotonia.

The influence of selected hypotensive drugs on the bioavailability of minerals from buckwheat groats in vitro enzymatic digestion

BACKGROUND

The mineral status in hypertensive patients may be affected by hypotensive drugs. The aim of this study was to estimate the influence of hypotensive drugs (angiotensine converting enzyme inhibitors (ACE-I), β-blockers, Ca-antagonists, diuretics) on the potential bioavailability of magnesium, iron, zinc and copper from buckwheat groats in vitro enzymatic digestion.

MATERIAL AND METHODS

The degree of release of magnesium, iron, zinc and copper from buckwheat groats was determined with and without (the control sample) an addition of hypotensive drugs. Four antihypertensive drugs in one dose (one tablet per sample) were analysed: metocard (a β-blocker), cardilopin (a Ca-antagonist), apo-perindox (ACE-I) and indapen (a diuretic). The samples were subjected to enzymatic digestion under in vitro conditions. The content of minerals in buckwheat groats before and after enzymatic digestion was determined by flame atomic absorption spectrometry (AAS).

RESULTS

It was found that cardilopin (amlodipine) and indapen (indapamide) significantly increased the release of zinc from groats. The degree of release of magnesium was higher and the release of iron was lower in samples with apo-perindox (perindopril) than in the control group. The release of copper was significantly decreased by indapen (indapamid).

CONCLUSIONS

Amlodipine, perindopril and indapamide affected the release of magnesium, iron, zinc and copper from buckwheat groats in vitro enzymatic digestion.

[Correction of aldosterone level as marker of RAAS dysfunction in patients with arterial hypertension degree II-III and chronic kidney diseases]

The hyperactivation of renin-angiotensin-aldosterone system (RAAS) underlies the development and the progression of arterial hypertension and chronic kidney diseases. Aldosterone is the main unit of RAAS and self-sufficient predictor of the development of cardiovascular events. In this study, the angiotensin receptor blocker valsartan, ACE inhibitor enalapril, and direct renin inhibitor aliskiren were used for the correction of blood pressure and aldosterone levels in patients with hypertension and chronic kidney diseases. The data obtained suggest that the proposed complex therapy provides the most complete blood pressure reduction and aldosterone level correction (as evidence of RAAS activity recovery), greatly improves the prognoses, and ensures maximum nephroprotection in the patients with arterial hypertension and chronic kidney diseases.

Effects of blood pressure lowering and intensive glucose control on the incidence and progression of retinopathy in patients with type 2 diabetes mellitus: a randomised controlled trial

AIMS/HYPOTHESIS

The aim of the present study was to investigate the effect of blood pressure lowering and intensive glucose control on the incidence and progression of retinopathy in type 2 diabetic patients.

METHODS

The Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) Retinal Measurements study, a substudy of ADVANCE, is a randomised (using a central, computer-based procedure) controlled 2 x 2 factorial trial comprising a double-blind comparison of blood pressure lowering with perindopril-indapamide vs placebo, and an open comparison of standard vs intensive glucose control targeting a HbA(1c) of < or = 6.5% in 1,602 diabetic patients from ADVANCE centres with access to retinal cameras conducted from 2001 to 2008. At baseline and the final visit, seven-field stereoscopic retinal photographs were taken and graded by blinded readers (gradeable baseline and final photographs from 1,241 patients). Progression of > or =2 steps in the Early Treatment of Diabetic Retinopathy Study classification (using the eye with worst grading) was the primary outcome.

RESULTS

Retinopathy progressed in 59 (4.8%) patients and developed in 128 (10.3%) patients over 4.1 years. Fewer patients on blood pressure-lowering treatment (n = 623) experienced incidence or progression of retinopathy compared with patients on placebo (n = 618), but the difference was not significant (OR 0.78; 95% CI 0.57-1.06; p = 0.12). Blood pressure-lowering treatment reduced the occurrence of macular oedema (OR 0.50; 95% CI 0.29-0.88; p = 0.016) and arteriovenous nicking compared with placebo (OR 0.60; 95% CI 0.38-0.94; p = 0.025). Compared with standard glucose control (n = 611), intensive glucose control (n = 630) did not reduce (p = 0.27) the incidence and progression of retinopathy (OR 0.84; 95% CI 0.61-1.15). Lower, borderline significant risks of microaneurysms, hard exudates and macular oedema were observed with intensive glucose control, adjusted for baseline retinal haemorrhages. These effects of the two treatments were independent and additive. Adverse events in the ADVANCE study are reported elsewhere.

CONCLUSIONS/INTERPRETATION

Blood pressure lowering or intensive glucose control did not significantly reduce the incidence and progression of retinopathy, although consistent trends towards a benefit were observed, with significant reductions in some lesions observed with both interventions.

TRIAL REGISTRATION

ClinicalTrials.gov ID no. NCT00145925.

FUNDING

Grants from Servier and the National Health and Medical Research Council of Australia.

[Endothelioprotective properties of L-arginine in a nitric oxide deficiency model]

In laboratory animals with endothelial dysfunction (nitric oxide deficiency) modeled by the introduction of NO-synthase inhibitor L-NAME, the activation of endothelioprotective effects of enalapril, lozartan, amlodipine, indapamide and nebivolol is revealed for their introduction in combination with L-arginine. This result was confirmed by the behavior of a generalizing parameter, the coefficient of endothelial dysfunction (CED) calculated using the results of tests on endothelium-dependent and -independent vasodilation.

Antihypertensive efficacy of indapamide SR in hypertensive patients uncontrolled with a background therapy: the NATIVE study

OBJECTIVES

Antihypertensive monotherapy rarely achieves blood pressure (BP) control. NATIVE (NATrilix SR use in combInation antihypertensiVe thErapy) evaluated indapamide sustained release (SR) in hypertensive patients receiving background therapy.

RESEARCH DESIGN AND METHODS

Patients remaining hypertensive (systolic BP [SBP], 145-180 mmHg; diastolic BP [DBP], 95-105 mmHg) while receiving an angiotensin-converting enzyme (ACE) inhibitor (n = 709), beta-blocker (n = 629), calcium-channel blocker (CCB; n = 493), angiotensin II type 1 receptor blocker (ARB; n = 75), alpha-blocker (n = 29) or other therapy (n = 6) were enrolled, recruited by physicians from 228 centres in Pakistan. Indapamide SR 1.5 mg was administered daily for 3 months with background therapy. BP was assessed every 2 weeks, and blood glucose and total cholesterol were evaluated at baseline and study end in a patient subgroup. Adverse events were also recorded.

MAIN OUTCOME MEASURES AND RESULTS

Of 2073 enrolled patients (49% males; mean age 51 years), 1941 received indapamide SR and background therapy. SBP and DBP decreased significantly (SBP, 166 +/- 16 mmHg at baseline vs. 132 +/- 12 mmHg at 3 months; DBP, 102 +/- 8 mmHg vs. 83 +/- 6 mmHg; both p < 0.0001 vs. baseline). Patients uncontrolled with an ACE inhibitor, beta-blocker, CCB or ARB achieved an SBP/DBP decrease of 34 +/- 15/19 +/- 9, 33 +/- 17/19 +/- 10, 33 +/- 15/18 +/- 8 or 35 +/- 16/20 +/- 12 mmHg, respectively (all p < 0.0001). In all, 84% of patients achieved target SBP (< or = 140 mmHg) and 61% achieved BP normalisation (SBP < 140, DBP < 90 mmHg). The absence of placebo control may lead to an overestimation of the extent of the BP reduction achieved. Glucose and cholesterol levels were unaffected by indapamide SR. Four percent of patients experienced side-effects, which were mild-to-moderate in severity.

CONCLUSIONS

In patients with hypertension despite antihypertensive therapy, indapamide SR significantly reduced BP with a good acceptability profile. Indapamide SR may represent an effective additional therapy for patients who do not achieve BP goals with other antihypertensive agents.

The efficacy of indapamid in different cardiovascular outcome – Meta-analysis

Bevezetés: Az első vonalba tartozó vérnyomáscsökkentőktől elvárható, hogy csökkentsék a cardiovascularis morbiditást és mortalitást. A thiazid vízhajtók ez irányú hatékonyságát több metaanalízisben leírták. Az indapamid hatásosságát bár számos tanulmány vizsgálja, eddig nem készült az összes adatot összefoglaló elemzés. Célkitűzés: az indapamid hatásosságát vizsgáló összes randomizált kontrollált vizsgálat adatainak szintézise. A tanulmányok eredményeit a különböző cardiovascularis és biztonsági végpontok szerint elemezzük. Módszer: A MEDLINE adatbázisban megkerestük az összes randomizált kontrollált indapamidvizsgálatot 1995 és 2005 között. Csak a kettős vak-, párhuzamos lebonyolítású vizsgálatokat vontuk be. Az adatok metaanalízisét állandó és véletlen hatású modellekben is elvégeztük, az eredményeket Mantel–Haenzel-próbával, inverz varianciapróbával teszteltük. Eredmények: 9 vizsgálat és 10 108 beteg adatait elemeztük. 48, stroke-on átesett beteg indapamidkezelésével megelőzhető egy újabb stroke-esemény (NNT = 47,8; 95%; KI: 29,6–126,6). 5 vizsgálatban 7085 beteg adatai alapján az indapamid a szisztolés vérnyomást 7,28 (95%; KI: 6,37–8,19), a diasztolés vérnyomást 3,50 Hgmm-rel (95%; KI 2,99–4,01) nagyobb mértékben csökkentette, mint a placebo. 5 vizsgálatban 2856 beteg szisztolés vérnyomását az indapamid 1,30 Hgmm-rel (95%; KI: 0,28–2,31) nagyobb mértékben csökkentette, mint az aktív kontroll, a diasztolés vérnyomáscsökkentés esetében nem volt szignifikáns különbség. 505 beteg adatai alapján az indapamid 6,50 g/m 2 -rel (95%; KI: 0,81–12,9) nagyobb mértékben csökkenti a bal kamrai izomtömegindexet, mint az enalapril. 6206 beteg követése során a gyógyszerhez köthető mellékhatások előfordulásának gyakorisága hasonló a placebóéhoz (rr = 0,97; 95%; KI: 0,76–1,22). Következtetések: Az indapamid hatásos az újabb stroke megelőzésében, hatékonyan csökkenti a vérnyomást és a bal kamrai izomtömegindexet. A kezelés biztonságosan alkalmazható.

Delapril plus indapamide: a review of the combination in the treatment of hypertension

Although many data indicate that the management of hypertension has improved over the last two decades, there is still a large proportion of hypertensive individuals who do not receive adequate management of their blood pressure (BP). Combination therapy with two or more antihypertensive agents from different drug classes is increasingly being recognised as the most effective means of achieving target BP values by pharmacological means, particularly in the large number of patients in whom monotherapy proves to be ineffective. Use of an angiotensin-converting enzyme (ACE) inhibitor combined with a diuretic is a well established antihypertensive combination that is very effective because of the different, yet synergistic, mechanisms of actions of agents from these two drug classes. Delapril is a potent antihypertensive ACE inhibitor, and indapamide is a thiazide-like diuretic with additional antihypertensive properties. The combination of delapril and indapamide provides renoprotective effects, and indapamide is also cardioprotective. Use of these two drugs together is therefore a rational selection for combination therapy, and one that has consistently demonstrated lowering of BP to target values with a level of efficacy that is at least as good as other combinations of ACE inhibitors and diuretics. This combination has also been found to provide favourable effects on haemodynamic parameters, including left ventricular mass index and ejection fraction. Furthermore, combining an ACE inhibitor and a thiazide-type diuretic has been associated with a decreased risk of stroke and is recommended for patients with cerebrovascular disease, a setting in which the combination of delapril and indapamide has therapeutic potential. Because of the additive mechanisms of delapril and indapamide, the dose required for an effective antihypertensive effect is relatively low, and the combination is well tolerated at such doses. In particular, metabolic effects normally associated with diuretics are rare at the therapeutic dose of indapamide used in combination with delapril, making the combination suitable for patients with metabolic disorders in whom diuretic therapy would otherwise not be recommended. Delapril 30 mg and indapamide 2.5mg have been combined in a fixed combination, offering the convenience of a one-tablet-per-day antihypertensive drug regimen for most patients, which, along with good tolerability, helps to address the issue of noncompliance.

Superior effect of an angiotensin-converting enzyme inhibitor over a diuretic for reducing aortic systolic pressure

BACKGROUND

In recent studies, benefit has been shown for angiotensin-converting enzyme (ACE) inhibitors and calcium antagonists over a beta-blocker in hypertension, through a greater reduction in aortic than brachial systolic and pulse pressure. No data are available on diuretics, even though these are the preferred initial treatment of patients with mild hypertension.

METHODS

In this study, 101 patients with mild essential hypertension were randomly assigned to an 8-week period of monotherapy with enalapril 10 mg a day or indapamide 2.5 mg a day. Central as well as brachial systolic, augmented, and pulse pressure were determined using SphygmoCor, as in the REASON and CAFE trials.

RESULTS

Enalapril and indapamide reduced brachial systolic, diastolic, mean and pulse pressure to the same extent, and the heart rate was unchanged. Although there was no difference in brachial pressure with enalapril and indapamide, enalapril caused a greater fall in estimated aortic systolic, and pulse pressures. The augmentation index, an index of wave reflection, fell from 33.7 to 28.3% with enalapril but was unchanged with indapamide.

CONCLUSION

Results infer a reduction in wave reflection with enalapril, causing a fall in aortic pressure augmentation, and a corresponding fall in aortic systolic and pulse pressure. These were not apparent from brachial cuff measurements. Results show that a diuretic, like a beta-blocker agent, is not as effective a therapy as an ACE inhibitor in reducing aortic systolic and pulse pressure, and that the difference is not attributable to a change in heart rate.

Persistence of the antihypertensive effect of low-dose combination therapy in mild hypertension

The persistence of the antihypertensive effect of perindopril 2 mg + indapamide 0.625 mg once daily for up to 72 h was evaluated using the "missed-dose" technique. After 4 weeks on perindopril 2 mg+indapamide 0.625 mg, 79 of 216 hypertensive patients at goal (diastolic blood pressure < 85 mmHg) continued on perindopril 2 mg+indapamide 0.625 mg for a further 8 weeks. During either week 9 or 11, placebo was substituted for perindopril 2 mg+indapamide 0.625 mg on either 1 day or on 2 consecutive days. Twenty-four-hour ambulatory blood pressure was recorded at baseline, after 9 or 11 weeks of perindopril 2 mg+indapamide 0.625 mg and during the simulated missed doses, 24-48 and 48-72 h after perindopril 2 mg+indapamide 0.625 mg. Significant (p < 0.001) reductions in mean (+/- SD) 24-h blood pressure (mmHg) during the first 24 h after perindopril 2 mg+indapamide 0.625 mg vs baseline were noted for the two sub-groups subsequently allocated to one missed dose (-13.5 +/- 10.4/-8.0 +/- 6.6) or two missed doses (-12.2 +/- 7.4/-6.9 +/- 4.2). The antihypertensive effect persisted (p < 0.001 to p < 0.05 vs baseline) on the days when placebo was substituted for perindopril 2 mg+indapamide 0.625 mg with reductions in mean 24-h blood pressure from 24-48 h and 48-72 h after dosing being -11.6 +/- 9.6/-6.3 +/- 6.4 and -6.4 +/- 6.0/-3.9 +/- 4.2, respectively. Use of the "missed-dose" technique demonstrated persistence of an antihypertensive effect for perindopril 2 mg + indapamide 0.625 mg for up to 72 h after dosing.

Chronic and acute effects of different antihypertensive drugs on femoral artery relaxations of L-NAME hypertensive rats

We aimed to compare the effects of chronic and acute administration of structurally different antihypertensives, diuretics - indapamide and hydrochlorothiazide, ACE inhibitor - captopril and indapamide+captopril combination on endothelium-dependent relaxation of femoral artery isolated from nitric oxide (NO)-deficient rats. In the chronic experiment, femoral artery was isolated from Wistar rats receiving L-NAME (40 mg/kg/day) solely or with indapamide (1 mg/kg/day), hydrochlorothiazide (10 mg/kg/day), captopril (10 mg/kg/day), and indapamide+captopril combination for seven weeks. In the acute in vitro experiment, the incubation medium with femoral artery isolated from L-NAME-hypertensive rats was supplemented with investigated antihypertensives in the same concentration 10(-4) mol/l. Interestingly, chronic L-NAME treatment did not cause a reduction of vasorelaxation. Indapamide+captopril elevated relaxation above the control level and completely prevented blood pressure increase induced by L-NAME. Acute incubation with captopril only or indapamide+captopril improved relaxation of femoral artery isolated from L-NAME-hypertensive rats, while the incubation with all antihypertensives increased vasorelaxation of femoral artery isolated from control Wistar rats. In conclusion, NO might be involved in the indapamide- and hydrochlorothiazide-induced improvement of vasorelaxation, while different vasorelaxing factors (prostacyclin, EDHF) contribute to the captopril-induced improvement of vasorelaxation. During the chronic treatment additive and synergic effects of indapamide and captopril may contribute to the prevention of hypertension and increase of vasorelaxation.

[Effect of a fixed combination of perindopril and indapamide on 24-hour blood pressure profile, morpho-functional parameters of the heart, heart rate variability, functional state of the kidney, and quality of life in patients with arterial hypertension combined with metabolic syndrome]

Therapy with the use of a fixed combination of perindopril and indapamide was prescribed to 22 patients with metabolic syndrome and I - II degree hypertension for 16 weeks. Examination at baseline and after treatment included 24-hour blood pressure (BP) monitoring, echocardiography, biochemical analysis of blood, study of functional state of the kidney, heart rate variability, and quality of life. Positive dynamics of 24-hour BP profile and renal function was revealed after treatment. The therapy affected positively geometry of the left ventricle and vegetative homeostasis, improved quality of life, lowered atherogeneity of blood plasma and did not change significantly level of fasting glycemia, i.e. was associated with high antihypertensive effect and exerted pronounced organoprotective action.

[Indapamide retard and enalapril in patients with arterial hypertension: hypotensive effectiveness and effect on endothelial function]

AIM

To find out what type of therapy was better for restoration of 24 hour blood pressure (BP) rhythm and impaired function of vascular endothelium, and to determine preferential therapy for patients with severe endothelial dysfunction.

METHODS

We performed ambulatory blood pressure monitoring and assessments of endothelial dependent (flow mediated-FM) and endothelial independent (nitroglycerine) dilatation of forearm artery (DFA) in patients with stage I-III essential hypertension. In a randomized comparative cross-over study 76 patients (mean age 49.2 +/- 6.2 years) received indapamide retard 1.5 mg and enalapril 20 mg for 24 weeks.

RESULTS

Hypotensive effect of both drugs was identical (indapamide lowered systolic/diastolic BP by 13.6/12.0% and 12.9/9.9%, enalapril lowered BP by 14/14.6% and 13.2/12.9%). BP rhythm was better transformed by treatment with indapamide: nocturnal fall of mean BP increased on indapamide from 8.1 +/- 6.9% at baseline to 12.8 +/- 5.0% after treatment, p=0.007, and on enalapril from 11.8 +/- 7.9% at baseline to 10.4 +/- 6.2% after treatment, p=0.2. Indapamide and enalapril significantly augmented FM DFA (from 4.7 +/- 2.8% to 9.03 +/- 3.47%, p < 0.001, and from 4.6 +/- 2.2% to 10.9 +/- 3.5%, p < 0.001, respectively). All patients were divided into 2 groups: with baseline FM DFA - 2.5% (group I, n=59) and < 2.5% (group II, n=16). In group II indapamide lowered BP more effectively than enalapril ( - 10.2/ - 9.1% and - 5.5/ - 5.2%, p < 0,01/0.01, respectively).

CONCLUSION

Both indapamide retard 1.5 mg and enalapril 20 mg exerted normalizing action on endothelium dependent DFA. However indapamide transformed 24 hour BP profile better than enalapril. Hypotensive therapy with indapamide was more effective than therapy with enalapril in patients with more pronouncedly disturbed FM arterial vasodilatation. This can be used in selection of a preparation in patients with impaired FM vasodilatation.

Protective Action of Indapamide, a Thiazide-Like Diuretic, on Ischemia-Induced Injury and Barrier Dysfunction in Mouse Brain Microvascular Endothelial Cells

The aim of the present study was to elucidate the effects of indapamide on ischemic damage to the blood-brain barrier (BBB) in vitro. The ischemia/reperfusion conditions employed here significantly decreased the viability of mouse brain capillary endothelial (MBEC4) cells, an effect ameliorated by indapamide. Ischemia increased the permeability of MBEC4 cells to two cellular transport markers, sodium fluorescein and Evan's blue-albumin. Indapamide reduced the ischemia-induced hyperpermeability of cells. These results suggest that indapamide may have a protective role against ischemia-induced injury and dysfunction of the BBB.

Lower target blood pressures are safe and effective for the prevention of recurrent stroke: the PROGRESS trial

OBJECTIVE

To explore the likely optimum blood pressure (BP) level for patients with a history of cerebrovascular disease.

METHODS

The Perindopril Protection Against Recurrent Stroke Study (PROGRESS) was a randomized, placebo-controlled trial that established the beneficial effects of BP lowering in 6105 patients with cerebrovascular disease. The present study comprises two series of post hoc analyses. The first was designed to investigate the effects of randomized treatment on recurrent stroke by baseline BP levels, and the second was a corresponding observational analysis investigating the association between achieved follow-up BP levels and recurrent stroke risk.

RESULTS

Analyses of the randomized treatment comparisons showed that BP lowering with combination therapy produced similar risk reductions in each of four subgroups defined by baseline BP of less than 120, 120-139, 140-159, and 160 mmHg or greater (P homogeneity = 0.5). The effects of single-drug therapy were also comparable across these subgroups (P homogeneity = 0.2), but consistently greater benefits were observed with combination compared to single-drug therapy. The analyses of achieved follow-up BP showed that the lowest risk of recurrence was among the one-quarter of participants with the lowest follow-up BP levels (median 112/72 mmHg), and that risks rose progressively with higher follow-up BP levels. Minor side-effects were progressively more common at lower BP levels (P homogeneity = 0.04), but there was no excess of serious complications (all P homogeneity > 0.2).

CONCLUSION

These analyses provide no evidence of a J-curve relationship between BP level and stroke risk among patients with cerebrovascular disease, and identify no patient group among whom more intensive BP lowering would not be expected to produce greater risk reductions.

Comparison of the effect of diuretics on carotid blood flow in stroke patients

OBJECTIVES

Indapamide (IND) and bendroflumethiazide (BDZ) are both widely used in the management of blood pressure after stroke. There are theoretical reasons why these agents may differ with regard to their cardiovascular effects. We compared the effect of these agents on blood pressure and cerebral blood flow in a group of stroke patients.

METHODS

In a prospective, randomized, double-blinded study we investigated the effect of 28 days' treatment with BDZ 2.5 mg od or IND 2.5 mg od on blood pressure and cerebral blood flow in a group patients with recent first-ever ischemic stroke. Using extracranial carotid and transcranial ultrasound we assessed carotid blood flow and intracranial hemodynamics.

RESULTS

All data are expressed as mean (SD). Twenty-five patients completed the protocol (age 68.8 +/- 10.6 y). Groups I (IND) and B (BDZ) comprised 13 and 12 patients, respectively. Groups were well matched for demography and baseline characteristics. Percent change in mean arterial pressure reduction from baseline was (I = -14.7 +/- 12.5, P < 0.001 vs. B = -7.7 +/- 9.16 mm Hg, P = 0.02). There was a trend toward increased carotid blood flow in both groups (I = +10% +/- 47, P = 0.4 vs. B = +33% +/- 47, P = 0.12). No significant change in middle cerebral artery mean flow velocity or pulsatility index was observed. There was no significant difference between the 2 drugs with regard to change in blood pressure (95% confidence interval for difference -2.5 to 16.3 mm Hg, P = 0.14) or carotid blood flow (95% confidence interval for difference -58 to 27 mL/s, P = 0.45).

CONCLUSIONS

Both diuretics reduced blood pressure to a similar and significant degree. There was no evidence of an adverse effect on cerebral blood flow or intracranial hemodynamics induced by either agent. No significant difference between the effect of IND and BDZ was observed.

Indapamide induces apoptosis of GH3 pituitary cells independently of its inhibition of voltage-dependent K+ currents

Indapamide blocks multiple voltage-dependent K+ currents (Kv) in the heart and Kv have an important role in cell proliferation and apoptosis, so the aim of this work was to study the effects of indapamide on Kv and the viability of GH3 cells. Indapamide inhibited Kv of GH3 cells and the inhibition was irreversible after a 10-min washout when more than 250 microM indapamide was used. Indapamide reduced the viability of GH3 cells in a concentration-dependent manner. The decreased cell viability was because indapamide induced cell apoptosis, or even necrosis at higher concentrations. HepG2 cells, which express no apparent Kv, were used to determine the association between inhibition of Kv and the apoptotic action of indapamide. Indapamide had a similar action on cell viability and apoptosis of HepG2 cells. 4-Aminopyridine, the voltage-dependent K+ channel blocker, inhibited Kv of GH3 cells but did not induce the cell apoptosis. We concluded that while indapamide inhibited Kv and induced apoptosis of GH3 cells, the apoptotic action of indapamide was not associated with its inhibition of Kv.

Indapamide SR versus candesartan and amlodipine in hypertension: the X-CELLENT Study

BACKGROUND

Reducing systolic blood pressure (BP) is of major benefit to patients with isolated systolic hypertension, but lowering normal diastolic BP may be harmful in terms of cardiovascular risk. Effects of different drugs on systolic BP, diastolic BP, and pulse pressure are therefore of interest.

METHODS

The NatriliX SR versus CandEsartan and amLodipine in the reduction of systoLic blood prEssure in hyperteNsive patienTs study (X-CELLENT) was a randomized, double-blind, placebo-controlled study comparing the effects of three drugs on these BP components. Patients with systolic-diastolic or isolated systolic hypertension (n = 1758) received indapamide (1.5 mg) sustained release (SR), candesartan (8 mg), amlodipine (5 mg), or placebo once daily for 12 weeks.

RESULTS

Compared to placebo all active treatments reduced all BP components significantly (P < .001). For the patients with isolated systolic hypertension (n = 388), the three treatments significantly reduced systolic BP, but only indapamide SR did not change diastolic BP and thus reduced pulse pressure significantly relative to placebo (P = .005). In an ancillary study using ambulatory BP monitoring (n = 576), all three treatments significantly reduced BP components during 24 h relative to placebo. Changes in systolic BP and pulse pressure were similar with the three treatments, but the reduction in diastolic BP was significantly smaller, and therefore more favorable, with indapamide SR compared with candesartan (P = .039). In patients with isolated systolic hypertension (n = 106), indapamide SR reduced 24-h systolic BP significantly more than amlodipine (P = .037), and only indapamide SR reduced 24-h pulse pressure significantly relative to placebo (P = .03). All three drugs were well tolerated.

CONCLUSIONS

This distinctive BP-lowering profile of indapamide SR seems highly beneficial when compared to the either of candesartan or amlodipine.

An overview of the pharmacology and clinical efficacy of indapamide sustained release

The relationship between blood pressure (BP) and cardiovascular risk is clearly established; hypertension increases the rate of cardiovascular. High systolic blood pressure (SBP) may be the main parameter involved in cardiovascular morbidity and mortality. The benefit of lowering BP, particularly with diuretics has been proven in many outcome studies. Indapamide, a thiazide-type diuretic, was available for many years at a dosage of 2.5 mg in an immediate release formulation. A new sustained release (SR) formulation has been developed in order to allow the same antihypertensive efficacy with a better acceptability profile. This paper reviews the pharmacology of indapamide 1.5 mg SR from the bench to the bedside. Indapamide has a dual mechanism of action: diuretic effect at the level of the distal tubule in the kidney and a direct vascular effect, both of which contribute to the antihypertensive efficacy of the drug. The SR formulation contains a hydrophilic matrix, which delivers a smoother pharmacokinetic profile. This avoids unnecessary plasma peak concentrations, which may be associated with side effects. Indapamide SR has now been extensively used in hypertensive patients, including those at increased risk, for example elderly or diabetic patients. It has been shown to decrease BP, particularly SBP, with 24-h efficacy, allowing a once-daily dosage. Studies have demonstrated BP lowering to be at least as effective as all major therapeutic classes including the more recent antihypertensive drugs. Beyond BP decrease, indapamide SR has also been shown to protect against hypertensive target-organ damage in the heart and the kidney and to have a favorable metabolic profile. A broad evidence-base has accumulated to support the benefit of indapamide 1.5 mg SR in hypertensive patients, alone or as part of combination therapy, as recommended by the majority of guidelines.

Efficacy of indapamide 1.5 mg, sustained release, in the lowering of systolic blood pressure

The relationship between the increase in blood pressure and the incidence of cardiovascular disease is well recognized today. Studies have shown that more attention should be paid to systolic blood pressure (SBP) in relation to cardiovascular risk and that therapeutic interventions should preferably focus on reducing SBP. The antihypertensive efficacy of indapamide 1.5 mg sustained release (indapamide SR), a low-dose thiazide-type diuretic, was assessed on SBP. Three randomized, double-blind, controlled studies were conducted with indapamide SR, over a period of 3 to 12 months. Elderly patients or patients with target-organ damage, hypertension and left ventricular hypertrophy (LVH) (LIVE study) or with type II diabetes with microalbuminuria (NESTOR study) showed a decrease in SBP varying from 22.7 to 31.8 mmHg. The treatment with indapamide SR resulted in a better or equivalent control of SBP than treatment with a standard dose of a true thiazide diuretic (hydrochlorothiazide), a calcium channel blocker (amlodipine), and an angiotensin-converting enzyme inhibitor (enalapril). No therapeutic escape was observed. All treatments showed good acceptability with no unexpected adverse event. In conclusion, indapamide SR is very effective in lowering SBP-a major independent cardiovascular risk factor-notably in hypertensive high-risk patients with LVH, the elderly and diabetics, when compared to major antihypertensive treatments. This SBP-lowering effect is maintained over the long term.

Preparation of indapamide slow-release pellets

During the process of developing a slow-release formulation of indapamide, researchers created a drug-containing pellet coated with Eudragit RS100 (Rohm GMbH & Co. KG, Darmstadt, Germany) to control the rate at which the drug was released. The two main variables were the agglomerants used in the pellet preparation and the amount of Eudragit RS100 used to coat them. The optimal outcome was indicated by the greatest number of drug-containing pellets recovered through an 18- to 24-mesh sieve and a satisfactory 24-hour release curve. The kinetics of dissolution fit the Higuchi kinetics model. Stability tests of the drug pellets showed no notable changes in the rate of drug release, related substances (mean byproducts or impurities from interactions or decompositions), and drug content.

Effects of Indapamide, a Thiazide-Like Diuretic, on Structure of Cerebral Arterioles in Hypertensive Rats

We examined the effects of indapamide, a thiazide-like diuretic, on cerebral arterioles in spontaneously hypertensive rats (SHR). The structure and mechanics of cerebral arterioles were examined in untreated Wistar Kyoto rats (WKY) and SHR that were untreated or treated for 3 months with a low (1 mg/kg per day) or a high (10 mg/kg per day) dose of indapamide. We measured pressure, diameter, and cross-sectional area of the vessel wall (CSA) in maximally-dilated (EDTA) cerebral arterioles. Treatment of SHR with the high dose of indapamide normalized cerebral arteriolar mean pressure (62+/-4 [mean+/-SEM] versus 59+/-3 mm Hg in WKY and 88+/-6 mm Hg in untreated SHR; P<0.05), pulse pressure (13+/-1 versus 10+/-1 mm Hg in WKY and 20+/-1 mm Hg in untreated SHR; P<0.05), and CSA (1080+/-91 versus 1100+/-48 microm2 in WKY and 1439+/-40 microm2 in untreated SHR; P<0.05). In contrast, treatment of SHR with the low dose of indapamide did not normalize arteriolar mean (72+/-3) and pulse pressure (20+/-1 mm Hg), but did normalize CSA (1091+/-52 microm2). Treatment with either dose of indapamide failed to increase external diameter in cerebral arterioles of SHR (89+/-4 and 92+/-4 microm, respectively, versus 103+/-6 microm in WKY and 87+/-4 microm in untreated SHR). Finally, treatment with indapamide attenuated the rightward shift of the stress-strain curve in SHR, suggesting that treatment with indapamide attenuated increases in distensibility of cerebral arterioles in SHR. These findings suggest that, whereas thiazide-like diuretics may not attenuate eutrophic inward remodeling of cerebral arterioles in SHR, they may attenuate hypertrophic inward remodeling via a mechanism unrelated to their pressor effects.

[Relationship between changes of endothelial vasodilator function, vascular and cardiac structure and derangements of blood pressure 24-hour profile]

AIM

To assess relationship between 24-hour blood pressure (BP) rhythm and structural and functional state of the heart and blood vessels.

MATERIAL AND METHODS

Echocardiography, sonography of carotid artery intima-media, and assessment of endothelium dependent (flow mediated) and endothelium independent (nitroglycerine) brachial artery vasodilatation were used in the study of 83 patients with stage I-II essential hypertension (mean age 49.2+/-6.2 years). Seventy four patients received indapamide and enalapril for 24 weeks.

RESULTS

According to results of 24-hour BP monitoring the patients were divided into 2 groups with normal (dippers) and abnormal (non-dippers) BP rhythm. Non-dippers compared with dippers had more pronounced lowering of endothelium-dependent autoregulation of arterial tone, bigger left ventricular mass thicker carotid artery wall. Linear correlation was found between changes of 24-hour BP rhythm and structural and functional parameters of the heart and vessels. More pronounced regression of their derangements occurred during antihypertensive therapy in those patients in whom normalization of 24-hour rhythm was achieved.

[Structural and functional changes of the microcirculation in hypertension: influence of pharmacological therapy]

The increased peripheral resistance in hypertension results from arteriolar vasoconstriction, increased media-to-lumen (M/L) ratio of small resistance arteries, and rarefaction (reduction in density) of microvessels. Numerous neurohumoral and hormonal factors are involved in causing structural and functional changes in the microcirculation in hypertension, including the renin-angiotensin-aldosterone system, remodelling of the extracellular matrix, increased growth of the smooth muscle cells of the media, and elevated collagen and fibronectin deposition. Although a wide variety of pharmacological agents can decrease blood pressure (BP) in hypertension, they vary in their ability to reverse structural and functional changes in the microcirculation. ACE inhibitors have consistently been shown to regress microvascular changes but findings with calcium antagonists have been variable and beta-adrenoceptor blockers appear to have no effect. In studies with ACE inhibitors, improvements in the M/L ratio and endothelial function of small resistance arteries have been recorded in both animal models of hypertension and human subcutaneous arteries obtained by biopsy of gluteal tissue from patients with essential hypertension. Recent studies with the very low-dose combination of perindopril and indapamide have indicated that these agents act synergistically to restore normal microvascularisation and reverse capillary rarefaction in the coronary circulation of hypertensive rats, and normalise coronary blood flow reserve in humans with hypertension. The additional benefit accruing from regression of structural and functional abnormalities in critical vascular beds such as coronary or renal circulations of patients with chronic hypertension may well become an important factor in selection of antihypertensive therapy, as complications such as ischaemic episodes and other target organ damage may be prevented and the BP-lowering effect of treatment may be extended such that it continues even after withdrawal. However, whether improvements in microcirculatory structure and function will be associated with improved morbidity and mortality outcomes in patients with chronic hypertension has yet to be firmly established.

Effects of antihypertensive therapy on hemorheological profiles in female hypertensive patients with initially low or high whole blood viscosity

This study was designed to examine changes of hemorheological parameters in essential arterial hypertension subjects following antihypertensive drug therapy. Eighty two female subjects were enrolled, and sub-divided into two groups based upon their high shear whole blood viscosity being lower (L) or higher (H) than normal controls. Equal numbers of L and H subjects were then treated for four weeks with one of four agents: angiotensin-converting enzyme inhibitor (ACE-inhibitor, Spirapril - 6 mg/day); calcium antagonist (Isradipin - 5 mg/day); beta-1-blocker (Talinolol - 100 mg/day); diuretic (Indapamide - 1.5 mg/day). Both prior to and following drug treatment for six weeks, hemorheological measurements included plasma viscosity; high and low shear whole blood viscosity, hematocrit, fibrinogen and RBC aggregation. Treatment with each of the four drugs significantly (p<0.05) reduced blood pressure in both the L and H groups. However, the hemorheological effects of antihypertensive drug therapy differed markedly between groups: plasma and whole blood viscosity were significantly elevated in the L groups whereas these parameters were significantly decreased in the H groups. Fibrinogen levels and RBC aggregation decreased in both groups, whereas hematocrit was unaffected. These results thus suggest that the rheologic effects of antihypertensive drug therapy depend strongly on the initial, pre-treatment status of the subject, and that for some subjects, such therapy can result in adverse hemorheological alterations.

Mechanisms of adrenergic control of sino-atrial node discharge

Among the mechanisms proposed for the increase in discharge of sino-atrial node (SAN) by norepinephrine (NE) are an increase in the hyperpolarization-activated current I(f) and in the slow inward current I(Ca,L). If I(f) is the primary mechanism, cesium (a blocker of I(f)) should eliminate the positive chronotropic effect of NE. If I(Ca,L), is involved, [Ca(2+)](o) should condition NE effects. We studied the electrophysiological changes induced by NE in isolated guinea pig SAN superfused in vitro with Tyrode solution (both SAN dominant and subsidiary pacemaker mechanisms are present) as well as with high [K(+)](o), higher Cs(+) or Ba(2+) (only the dominant pacemaker mechanism is present). In Tyrode solution, NE (0.5-1microM) increased the SAN rate and adding Cs(+) (approximately 12 mM) caused a decaying voltage tail during diastole in subsidiary pacemakers. NE enhanced the Cs(+)-induced tail, and increased the rate but less than in Tyrode solution. In higher [Cs(+)](o) (15- 18 mM), Ba(2+) (1 mM) or Ba(2+) plus Cs(+) (10 mM) dominant action potentials (not followed by a tail) were present and NE accelerated them as in Tyrode solution. In high [K(+)](o), NE increased the rate in the absence and presence of Cs(+), Ba(2+) or Ba(2+) plus Cs(+). In these solutions, NE increased the overshoot and maximum diastolic potential of dominant action potentials (APs) and increased the rate by steepening diastolic depolarization and shifting the threshold for upstroke to more negative values. High [Ca(2+)](o) alone increased the rate and NE enhanced this action, whereas low [Ca(2+)](o) reduced or abolished the increase in rate by NE. In SAN quiescent in high [K(+)](o) plus indapamide, NE induced spontaneous discharge by decreasing the resting potential and initiating progressively larger voltage oscillations. Thus, NE increases the SAN rate by acting primarily on dominant APs in a manner consistent with an increase of I(Ca,L) and I(K) and under conditions where I(f) is either blocked or not activated. NE INITIATES spontaneous discharge by inducing voltage oscillations unrelated to I(f).

Effects of four antihypertensive monotherapies on cardiac mass and function in hypertensive patients with left ventricular hypertrophy: randomized prospective study

AIM

To compare the effects of four antihypertensive drugs, which have reportedly different effectiveness in reducing myocardial mass.

METHODS

A randomized, double-blind, prospective study included 80 hypertensive patients with left ventricular (LV) hypertrophy confirmed both electrocardiographically and echocardiographically. We investigated the effects of indapamide, nicardipine, propranolol, and chlorthalidone on arterial blood pressure and LV mass and function.

RESULTS

Sixty-four patients (34 men and 30 women) completed the 6-month study. No significant differences in antihypertensive effects of the four medications were found. The average decrease in systolic and diastolic blood pressure was 12.8% and 10.4%, respectively. All four antihypertensive medications caused pronounced reduction in LV mass, between 7.9% in the propranolol group and 10.1% in the nicardipine group, with no significant difference between the groups. In patients receiving diuretics, predominant decrease was observed in LV mass and LV mass index. In patients treated with propranolol, the thickness of both the LV wall and interventricular septum was reduced, whereas the reduction in LV mass, LV wall and interventricular septum thickness was found in patients treated with nicardipine. There was no significant correlation between the changes in LV mass and other variables (blood pressure, and systolic and diastolic function). Systolic function did not improve with the reversion of LV hypertrophy in any group of patients, but improvement was observed in some indices of diastolic function. The early and late LV filling velocity and their ratio did not improve significantly, either. Clinically relevant side effects were not observed.

CONCLUSION

All four antihypertensive monotherapies achieved a comparable control of hypertension and reduction in LV hypertrophy.

Metabolic profile of indapamide sustained-release in patients with hypertension: data from three randomised double-blind studies

OBJECTIVE

To evaluate the influence of indapamide sustained-release (SR) 1.5 mg/day, a thiazide-related sulfonamide diuretic, on serum levels of lipids (total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol and triglycerides), glucose and uric acid, and renal function (serum urea and creatinine levels).

METHODS

Pooled data from three randomised, double-blind, controlled studies are analysed. Two of these studies were of short duration (2 and 3 months), one of which included a 9-month nonblind extension phase, and the third was a 12-month prospective study. Short- and long-term metabolic effects of the treatment could thus be analysed. All studies were conducted in patients with mild-to-moderate hypertension; the total population randomised in these studies comprised 1195 patients, of whom 505 had left ventricular hypertrophy (LVH).

RESULTS

After 2 to 3 months' treatment with indapamide SR 1.5 mg/day, there was no significant change from baseline in serum lipid levels and glucose levels. This neutral effect was maintained after 9 and 12 months of treatment. Renal function was not affected by short- or long-term indapamide SR 1.5 mg/day therapy. Serum uric acid level was slightly increased after short-term therapy, but was restored to baseline values during long-term therapy with indapamide SR 1.5 mg/day.

CONCLUSIONS

Indapamide SR 1.5 mg/day has no deleterious effect on glucose metabolism, serum levels of lipids and uric acid, or renal function. This antihypertensive agent can be considered to be an attractive therapeutic choice for all patients with mild-to-moderate hypertension, including the elderly and patients with increased cardiovascular risks, i.e. those with LVH.

Molecular and functional characterization of ERG, KCNQ, and KCNE subtypes in rat stomach smooth muscle

Contribution of K(+) channels derived from the expression of ERG, KCNQ, and KCNE subtypes, which are responsible for rapidly and slowly activating delayed rectifier K(+) currents (I(Kr) and I(Ks), respectively) in cardiac myocytes, to membrane currents was examined in stomach circular smooth muscle cells (SMCs). The region-qualified multicell RT-PCR showed that ERG1/KCNE2 transcripts were expressed in rat stomach fundus and antrum SMCs and that KCNQ1/KCNE1 transcripts were expressed in antrum but not fundus. Western blotting and immunocytochemical analyses indicate that ERG1 proteins were substantially expressed in both regions, whereas KCNE1 proteins were faintly expressed in antrum and not in fundus. Both I(Kr)- and I(Ks)-like currents susceptible to E-4031 and indapamide, respectively, were identified in circular SMCs of antrum but only I(Kr)-like current was identified in fundus. It is strongly suggested that I(Kr)- and I(Ks)-like currents functionally identified in rat stomach SMCs are attributable to the expression of ERG1/KCNE2 and KCNQ1/KCNE1, respectively. The membrane depolarization by 1 microM E-4031 indicates the contribution of K(+) channels encoded by ERG1/KCNE2 to the resting membrane potential in stomach SMCs.

Perindopril/indapamide 2/0.625 mg/day: a review of its place in the management of hypertension

The fixed low-dose combination of the ACE inhibitor perindopril and the non-thiazide diuretic indapamide has been evaluated in the management of patients with mild to moderate hypertension. Combination therapy aims to improve overall therapeutic efficacy while minimising adverse effects. In well-designed multicentre clinical trials, perindopril/indapamide at doses ranging from 2/0.625 to 8/2.5 mg/day was significantly more effective than placebo in achieving adequate blood pressure (BP) control. A similar reduction in supine BP was observed when combined perindopril/indapamide 2/0.625 mg/day was compared with losartan 50 mg/day or atenolol 50 mg/day. Similar reductions in 24-hour ambulatory BP were also seen with perindopril/indapamide 2/0.625 mg/day and irbesartan 150 mg/day. However, response and normalisation rates were significantly higher with combination therapy than with losartan or irbesartan monotherapy. Combined perindopril/indapamide 2/0.625 mg/day therapy effectively reduced BP in elderly patients aged 65 to 85 years to a significantly greater extent than either atenolol 50 mg/day or placebo. Supine BP was also normalised in approximately two-thirds of patients in a small noncomparative trial in patients with hypertension and renal impairment. Low-dose perindopril/indapamide 2/0.625 mg/day was well tolerated in clinical trials; the most common adverse events were headache and cough. Hypokalaemia, associated with the use of diuretics, occurred with a higher incidence with combined perindopril/indapamide 2/0.625 mg/day therapy than with either atenolol 50 mg/day or placebo. Perindopril/indapamide 2/0.625 mg/day has shown efficacy in well designed comparative trials with atenolol, losartan and irbesartan including elderly patients and patients with renal impairment. Studies comparing this dosage of perindopril/ indapamide with other combination therapies would be beneficial in allowing the place of perindopril/indapamide to be more accurately determined. The fixed-low dose combination of perindopril/indapamide provides a promising and well tolerated treatment option in the management of patients with mild to moderate hypertension.

[Clinical study of the month. Secondary prevention of cerebrovascular accident with perindopril: the PROGRESS study]

PROGRESS ("Perindopril pROtection aGainst REcurrent Stroke Study") demonstrated that blood-pressure lowering treatment with perindopril, an angiotensin converting enzyme inhibitor (combined with the diuretic agent indapamide when necessary), reduces the risk of stroke by 28% (95% CI: 17-38, p < 0.0001) among patients with a history of stroke or transient ischaemic attack. This protective effect was observed among both hypertensive and non-hypertensive individuals. It was more marked in the patients receiving combined perindopril + indapamide treatment (-43%; 95% CI 30-54) who were those who showed the greatest reduction in arterial blood pressure (-12/5 mm Hg). According to these observations, the authors concluded that treatment with these two agents should now be considered routinely for patients with a history of stroke or transient ischaemic attack, irrespective of their blood pressure.

Sodium intake, large artery stiffness, and proteoglycans in the spontaneously hypertensive rat

Although the role of sodium in hypertension has been documented extensively, its effect on large arteries has not been well documented. We examined the effect of high-sodium (8%) diet and the diuretic indapamide (IND) on systemic hemodynamics and aortic wall structure and composition in collagen, elastin, and hyaluronan. Four groups of spontaneously hypertensive rats (SHR) were studied after 8 weeks: those on a normal diet (SHR), a high-sodium diet (SHR+NaCl), a normal diet with IND (SHR+IND), and a high-sodium diet with IND (SHR+NaCl+IND). Mean BP, which was not normalized with IND, was comparable for all groups. Systemic arterial compliance averaged 3.8, 2.5, 4.9, and 3.3 mL/mm Hg. 10(-3), respectively, for the SHR, SHR+NaCl, SHR+IND, and SHR+NaCl+IND groups (P<0.003 and <0.05 for NaCl and IND effects). Wall thickness increased only in the SHR+NaCl group (P<0.01). Aortic wall COL decreased from 16 116 in the SHR to 12 382 micrometer(2)/mm in the SHR+NaCl+IND (P<0.005) group. IND alone had no effect on elastin, but the elastin/collagen ratio was increased significantly. Aortic hyaluronan averaged 2343, 266, 3243, and 1052 micrometer(2)/mm, respectively, for the SHR, SHR+NaCl, SHR+IND, and SHR+NaCl+IND groups (P<0.0001 for NaCl and IND effects). Changes in systemic arterial compliance were significantly and positively correlated with aortic hyaluronan contents. Thus, high-sodium diet affects the structural and functional characteristics of large arteries independently of BP. A high-sodium diet, in addition to a diuretic regimen with IND, affects simultaneously aortic hyaluronan contents and large artery mechanical properties through pressure-independent mechanisms that remain to be defined.

Growth inhibitory activity of indapamide on vascular smooth muscle cells

Abnormal vascular smooth muscle cell proliferation has a fundamental role in the pathogenesis of vascular diseases. Indapamide is an oral diuretic antihypertensive drug effective for patients with mild or moderate essential hypertension. We now investigated the effects of indapamide on the growth of aortic vascular smooth muscle cells (A10 cell line). Indapamide inhibited cell proliferation as measured by the tetrazolium salt XTT (sodium 3'-[1-(phenylamino-carbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro)benzene sulfonic acid hydrate) test. The increase in cell number was significantly reduced in the presence of indapamide 10(-6) and 5 x 10(-4) M (P < 0.05 n = 3 and P < 0.01, n = 3, respectively). Serum-induced DNA synthesis, determined as the incorporation of 5-bromo-2'-deoxyuridine (BrdU), was concentration-dependently inhibited by indapamide. BrdU incorporation was 47.2+/-1.6% (10% foetal calf serum). Indapamide treatment markedly prevented BrdU incorporation (37.2+/-2.1%, 29.2+/-4.8%, 15.0+/-1.8%, 8.7+/-2.1%) indapamide 10(-6), 10(-5), 5 x 10(-5) and 5 x 10(-4) M, respectively. Cell-cycle progression was also evaluated. Flow cytometry analysis of DNA content in synchronised cells revealed blocking of the serum-inducible cell-cycle progression by indapamide. This inhibition was abolished when the drug was added 2 h after serum repletion, indicating that indapamide must act at the early events of a cell cycle to be fully effective against DNA synthesis. In addition, serum-induced intracellular Ca2+ movements and also p44/p42 mitogen-activated protein kinase (MAPK) phosphorylation were studied in the presence or absence of indapamide. Indapamide 10(-5) and 5 x 10(-5) M decreased significantly cytosolic free calcium, and the p44/p42 mitogen-activated protein kinase phosphorylation (5 x 10(-5) M) stimulated by 10% foetal calf serum. In accordance with this finding, indapamide (5 x 10(-4) M) caused a 95% to 99% decrease in the early elevation of c-fos expression as evaluated by northern blot analysis of mRNA induced after serum addition. In conclusion, our results indicate that indapamide reduces vascular smooth muscle cell proliferation by a mechanism which involves a decrease in the intracellular Ca2+ movements that might link with the mitogen-activated protein kinase (MAPK) pathway, altering cell-cycle progression.

Functional consequences of the arrhythmogenic G306R KvLQT1 K+ channel mutant probed by viral gene transfer in cardiomyocytes

IKs, the slow component of the delayed rectifier potassium current, figures prominently in the repolarization of heart cells. The K+ channel gene KvLQT1 is mutated in the heritable long QT (LQT) syndrome. Heterologous coexpression of KvLQT1 and the accessory protein minK yields an IKs-like current. Nevertheless, the links between KvLQT1 and cardiac IKs are largely inferential. Since the LQT syndrome mutant KvLQT1-G306R suppresses channel activity when coexpressed with wild-type KvLQT1 in a heterologous system, overexpression of this mutant in cardiomyocytes should reduce or eliminate native IKs if KvLQT1 is indeed the major molecular component of this current. To test this idea, we created the adenovirus AdRMGI-KvLQT1-G306R, which overexpresses KvLQT1-G306R channels. In > 60 % of neonatal mouse myocytes, a sizable IKs could be measured using perforated-patch recordings (8.0 +/- 1.6 pA pF-1, n = 13). IKs was increased by forskolin and blocked by clofilium or indapamide but not by E-4031. While cells infected with a reporter virus expressing only green fluorescent protein (GFP) displayed IKs similar to that in uninfected cells, AdRMGI-KvLQT1-G306R-infected cells showed a significantly reduced IKs (2.4 +/- 1.1 pA pF-1, n = 10, P < 0.01) when measured 60-72 h after infection. Similar results were observed in adult guinea-pig myocytes (5.9 +/- 1.2 pA pF-1, n = 9, for control vs. 0.1 +/- 0.1 pA pF-1, n = 5, for AdRMGI-KvLQT1-G306R-infected cells). We conclude that KvLQT1 is the major molecular component of IKs. Our results further establish a dominant-negative mechanism for the G306R LQT syndrome mutation.

Effects of combination of low doses of angiotensin-converting enzyme inhibitor and diuretics on renal function in spontaneously hypertensive rats: comparison between acute and chronic treatment

The goal of this study was to assess the effect of acute or chronic treatment with S5590, a combination of the angiotensin-converting enzyme inhibitor perindopril (0.76 mg/kg/day) and the diuretic indapamide (0.24 mg/kg/day) on renal function in spontaneously hypertensive rats with moderate renal injury. Renal function was evaluated in conscious rats by clearance methods using labelled inulin and PAH, after catheterisation of the carotid artery, jugular vein and bladder. Both acute and chronic treatment normalised renal vascular resistance, although the effect on blood pressure was more marked after chronic than after acute treatment. Although acute treatment with S5590 increased glomerular filtration rate and renal blood flow, chronic treatment did not affect these parameters. Diuresis and natriuresis were only slightly modified and the results suggest a marked renal vasodilatation. In conclusion, the maintenance of renal function after chronic treatment, in a setting of normalisation of arterial pressure, suggest that such a combined treatment may exert marked renal functional protective effects in hypertension.

Indapamide, a thiazide-like diuretic, decreases bone resorption in vitro

We recently showed that indapamide (IDP), a thiazide-related diuretic, increases bone mass and decreases bone resorption in spontaneously hypertensive rats supplemented with sodium. In the present study, we evaluated the in vitro effects of this diuretic on bone cells, as well as those of hydrochlorothiazide (HCTZ), the reference thiazide, and acetazolamide (AZ), a carbonic anhydrase (CA) inhibitor. We showed that 10(-4) M IDP and 10(-4) M AZ, as well as 10(-5) M pamidronate (APD), decreased bone resorption in organ cultures and in cocultures of osteoblast-like cells and bone marrow cells in the presence of 10(-8) M 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. We investigated the mechanism of this antiresorptive effect of IDP; IDP decreased osteoclast differentiation as the number of osteoclasts developing in coculture of marrow and osteoblast-like cells was decreased markedly. We then investigated whether IDP affected osteoblast-like cells because these cells are involved in the osteoclast differentiation. Indeed, IDP increased osteoblast-like cell proliferation and alkaline phosphatase (ALP) expression. Nevertheless, it did not modify the colony-stimulating factor 1 (CSF-1) production by these cells. In addition, osteoblast-like cells expressed the Na+/Cl- cotransporter that is necessary for the renal action of thiazide diuretics, but IDP inhibited bone resorption in mice lacking this cotransporter, so the inhibition of bone resorption and osteoclast differentiation did not involve this pathway. Thus, we hypothesized that IDP may act directly on cells of the osteoclast lineage. We observed that resorption pits produced by spleen cells cultured in the presence of soluble osteoclast differentiation factor (sODF) and CSF-1 were decreased by 10(-4) M IDP as well as 10(-5) M APD. In conclusion, in vitro IDP increased osteoblast proliferation and decreased bone resorption at least in part by decreasing osteoclast differentiation via a direct effect on hematopoietic precursors.

Direct vascular actions of methyclothiazide and indapamide in aorta of spontaneously hypertensive rats

In vitro experiments were designed to assess the inhibitory effect of the thiazide diuretics methyclothiazide (MCTZ), the hydrochlorothiazide (HCTZ), and the thiazide-related diuretic indapamide (IND) on contractile responses to norepinephrine (NE) and arginine vasopressin (AVP) of aortic rings from spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto rats (WKY). Changes in the tension of aortic ring preparations were measured isometrically. MCTZ (10(-4) M) induced endothelium-dependent inhibition of the vasoconstrictor responses to NE and AVP only in aortas from SHR, and the maximal vasoconstrictive effect of NE and AVP was decreased by 59 +/- 11% and 32.3 +/- 13%, respectively. Indapamide (10(-4) M) also induced endothelium-dependent inhibition of the contractile response to AVP in aortic rings from SHR, and the maximal vasoconstrictive effect of AVP was decreased by 33 +/- 5%. In contrast, HCTZ did not inhibit the contractile response to either NE or AVP, even at the highest concentration. This study provides evidence that methyclothiazide and indapamide inhibit the contractile response induced by norepinephrine and/or arginine vasopressin on SHR aortic preparations via an endothelium-dependent mechanism.

Ambulatory blood pressure profiles in patients treated with once-daily diltiazem extended-release or indapamide alone or in combination

This randomized, double-blind, placebo-controlled, parallel-group study evaluated the efficacy and safety of single daily dose diltiazem extended-release (XR) and indapamide, given alone and combined, in 255 male and 170 female patients with mild to moderate hypertension. Blood pressure was assessed both manually in the office and by 24-hour ambulatory blood pressure monitoring (ABPM) techniques. Between-treatment efficacy comparisons were based on ABPM plots and changes from baseline in supine systolic (SuSBP) and diastolic (SuDBP) blood pressure after 6 weeks of double-blind treatment. Periodic 12-lead electrocardiograms (ECG), clinical laboratory tests, and physical examinations were used to assess safety. Both diltiazem XR 180, 240, and 360 mg and indapamide 2.5 mg monotherapy reduced ambulatory blood pressure to a greater extent than placebo. The ABPM data demonstrate that 2.5 mg indapamide produces an additional reduction in diastolic blood pressure when combined with fixed doses of diltiazem XR (120, 180, and 240 mg). The reduction was consistent over the entire 24-hour recording period for all combinations. Compared with monotherapy groups, higher therapeutic response rates (SuDBP < or = 90 mm Hg or Delta SuDBP > or = 10 mm Hg decrease from baseline) were also observed with combination therapy. Office blood pressure data qualitatively and quantitatively supported the observations made from the ABPM data. There were no unexpected adverse events or side-effect trends and no dose-response or clinically significant laboratory, ECG, or physical examination adverse effects. The combination therapy regimens were well tolerated with safety profiles comparable with those of the individual therapies.

Vasodilatory effect of diuretics is dependent on inhibition of vascular smooth muscle carbonic anhydrase by a direct mechanism of action

Five years ago, our in vitro and in vivo studies demonstrated for the first time that diuretic agents such as furosemide, hydrochlorothiazide, amiloride, triamterene and spironolactone inhibit carbonic anhydrase (CA) I, II and renal CA IV by a direct mechanism of action. In this paper we investigate the relationship between diuretics and CA I in the vasodilatory mechanism. Both in vitro (on purified CA I, erythrocyte CA I and smooth muscle CA I) and in vivo (in human and rabbits) we studied the effect of acetazolamide, hydrochlorothiazide, indapamide, furosemide, amiloride and triamterene on purified CA I, on human erythrocyte CA I, as well as on CA I isolated from vascular smooth muscle. Our results demonstrate that in vitro all diuretics inhibit CA I by a direct mechanism of action. Inhibition reached 100% with acetazolamide, 45% with hydrochlorothiazide, 82% with indapamide, 85% with furosemide, 68% with amiloride and 58% with triamterene. In vivo, similar inhibition of erythrocyte and smooth muscle CA I was obtained, being parallel with a reduction in arterial blood pressure values. Our data show that in addition to their already known mechanisms, diuretics also inhibit CA in vascular smooth muscle. Our results suggest that this mechanism is achieved by means of pH changes induced by CA I inhibition.