Efecto de las variantes de CYP2C9 sobre la dosis de losartán en hipertensos chilenos / Association between cytochrome p4502c9 polymorphisms and losartan dosing in hypertensive patients

Background Losartan is widely used in many clinicals settings. Its dosage is related to the genetic characteristics of CYP2C9 enzymatic activity, which metabolizes losartan to its active form E-3174, responsible for the antihypertensive effect. Aims To identify the frequency of allelic variants CYP2C9*2 and CYP2C9*3 in hypertensive patients and to compare genotypes with a healthy Chilean population. To relate polymorphisms with the losartan dosing to obtain an optimal blood pressure. Material and Methods We studied 30 patients with controlled essential hypertension using losartan with normal liver function, and 202 healthy people. Peripheral blood DNA genotyping was performed by polymerase chain reaction to identify the polymorphisms. Allelic and genotypic frequencies were compared. Results In hypertensive patients, allelic frequencies were 0.85 (CYP2C9*1), 0.05 (CYP2C9*2) and 0.1 (CYP2C9*3). Genotypic frequencies were 73.3% (CYP2C9*1/*1), 6.7% (CYP2C9*1/*2), 16.7% (CYP2C9*1/*3) and 3.3% (CYP2C9*2/3); observing a significantly higher frequency of the allele CYP2C9*3 (p=0.041) and CYP2C9*1/*3 genotype (p=0.04). A non-significant tendency to need a larger dose of losartan was observed with the CYP2C9 * 3 allele, with an odds ratio (OR) of 1.46 (95% confidence intervals (CI) 0.01-18.64). The same tendency was observed with the need to use losartan twice a day, obtaining an OR of 5.88 (CI 0.54 -62.14). Conclusions There could be a relationship between the presence of CYP2C9 polymorphisms and the pathogenesis of hypertension. The presence of CYP2C9*3 is associated with the need for higher doses of losartan, possibly due to a decrease in the conversion of losartan to E-3174.

Prescripción de fármacos bloqueadores del sistema renina angiotensina en pacientes con enfermedad renal crónica etapa 3 en atención primaria de salud / Prescription of renin-angiotensin-aldosterone system blockers in patients with stage 3 chronic kidney disease

Background: To reduce the progression of chronic kidney disease (CKD) and cardiovascular risk, the guidelines recommend the blockade of the renin-angiotensin-aldosterone system (RAAS) in patients with proteinuria. Aim: To assess the frequency of enalapril or losartan use in diabetics or hypertensive patients with stage 3 CKD. Material and Methods: Review of clinical records of patients with CKD in an urban primary care clinic. Results: We identified 408 subjects aged 40 to 98 years (66% women) with stage 3 CKD. Sixty six percent had only hypertension and 34% were diabetic with or without hypertension. Seventy four percent received RAAS blockers (52% used enalapril, 45% losartan and 2% both medications). RAAS blockers were used in 70% of hypertensive and 78% of diabetic patients. The prescription in hypertensive diabetics with microalbuminuria was lower than in those without microalbuminuria (72% vs 87%, p < 0.05), but the opposite occurred in pure hypertensive patients with and without microalbuminuria (88% vs 69%, p < 0.05). There were no significant differences in blood pressure levels, microalbuminuria or serum potassium levels between RAAS blocker users and non-users. No differences were observed either between enalapril and losartan users. Conclusions: The adherence to clinical guidelines is insufficient and users of the recommended drugs did not achieve the expected goals.

Comparison of the efficacy of losartan, hydrocortisone and acetylsalicylic acid (ASA) in preventing the development of fibrous scar tissue in skeletal muscle / Comparação da eficácia de losartana, hidrocortisona e ácido acetilsalicílico (AAS) na prevenção do desenvolvimento de tecido cicatricial fibroso nos músculos esqueléticos / Comparación de la eficacia de losartán, hidrocortisona y ácido acetilsalicílico (AAS) en la prevención del desarrollo de tejido cicatricial fibroso en los músculos esqueléticos

OBJECTIVE: To analyze fibrous scar tissue inhibition capacity with the use of losartan, hydrocortisone and acetylsalicylic acid. METHOD: The sample consisted of 120 male heterogeneic Wistar rats with a muscle laceration model. The rats were divided into four groups of 30 animals each: control group, losartan group, ASA group and hydrocortisone group. The animals were anesthetized and a 2.5 cm longitudinal incision was made in the left thoracolumbar paravertebral region. The muscles were subjected to a Grade III lesion caused by applying Kelly hemostatic forceps for 60 seconds, followed by sectioning with scissors. The skin was sutured with 3-0 nylon monofilament thread. The animals were placed in individual cages with plenty of food and water. The losartan group received losartan diluted in water at a dose of 0.1 mg/mL (10 mg/kg/day), the ASA Group received a 3 mg/mL ASA solution (300 mg/kg/day), and the hydrocortisone group received a 0.2 mg/mL hydrocortisone solution (20 mg/kg/day). RESULTS: The control, losartan, hydrocortisone and aspirin groups had a fibrotic area of 0.95 ± 0.35 mm, 0.55 ± 0.34 mm, 0.93 ± 0.33 mm, and 0.66 ± 0.36 mm, respectively. We observed a significantly smaller fibrotic area in the losartan group compared to the control (p=0.01) and hydrocortisone (p=0.01) groups. There were no significant differences among the other groups. CONCLUSION: The healing of striated skeletal muscle produced less fibrous scar tissue when exposed to losartan in comparison to the control group or the hydrocortisone group. Level of Evidence I; Randomized double-blind placebo-controlled study.

OBJETIVO: Analisar a capacidade de inibição de formação de tecido cicatricial fibroso com losartana, hidrocortisona e AAS. MÉTODOS: A amostra consistiu em 120 ratos Wistar heterogênicos machos com modelo de laceração muscular. Os ratos foram distribuídos em quatro grupos de 30 animais: grupo controle, grupo losartana, grupo AAS e grupo hidrocortisona. Os animais foram anestesiados e submetidos a uma incisão em sentido longitudinal de 2,5 cm de extensão na região paravertebral toracolombar esquerda, e os músculos sofreram uma lesão grau III com pinça hemostática de Kelly durante 60 segundos e posterior secção com tesoura. A pele foi suturada com nylon monofilamentar 3-0. Os animais foram colocados em gaiolas individuais, com água e alimento à vontade. O grupo losartana recebeu losartana diluída em água na dose de 0,1 mg/ml (10 mg/kg/dia), o grupo AAS recebeu solução de AAS 3 mg/ml (300 mg/kg/dia), o grupo hidrocortisona recebeu solução de hidrocortisona 0,2 mg/ml (20 mg/kg/ dia). RESULTADOS: Os grupos controle, losartana, hidrocortisona e AAS apresentaram área fibrótica de0,95 ± 0,35 mm, 0,55 ± 0,34 mm, 0,93 ± 0,33 mm, 0,66 ± 0,36 mm, respectivamente. Observou-se área fibrótica significativamente menor do grupo losartana em comparação com o grupo controle (p = 0,01) e hidrocortisona (p = 0,01). Nos demais grupos não houve diferença significativa. CONCLUSÃO: A cicatrização do músculo estriado esquelético produziu menos tecido cicatricial fibroso quando exposto à losartana do que quando comparado com o grupo controle ou o grupo hidrocortisona. Nível de Evidência I; Estudo duplo-cego randomizado controlado por placebo.

OBJETIVO: Analizar la capacidad de inhibición de formación de tejido cicatricial fibroso con losartán, hidrocortisona y AAS (ácido acetilsalicílico). MÉTODOS: La muestra consistió en 120 ratas Wistar heterogéneas machos con modelo de laceración muscular. Las ratas fueron distribuidas en cuatro grupos de 30 animales: grupo control; grupo losartán; grupo AAS y grupo hidrocortisona. Los animales fueron anestesiados y sometidos a una incisión longitudinal de 2,5 cm de extensión en la región paravertebral toracolumbar izquierda y los músculos sufrieron una lesión de grado III con pinza hemostática de Kelly durante 60 segundos y posterior sección con tijera. La piel se suturó con monofilamento de nylon 3-0. Los animales fueron dispuestos en jaulas individuales con abundante comida y agua. El grupo losartán recibió losartán diluido en agua a una dosis de 0,1 mg/ml (10 mg/kg/día), el grupo AAS recibió solución de AAS de 3 mg/ml (dosis 300 mg/kg/día), el grupo hidrocortisona recibió solución hidrocortisona de 0,2 mg/ml (20 mg/kg/día). RESULTADOS: Los grupos control, losartán, hidrocortisona y AAS mostraron área fibrótica de 0,95 ± 0,35 mm, 0,55 ± 0,34 mm, 0,93 ± 0,33 mm, 0,66 ± 0,36 mm, respectivamente. Se observó área fibrótica significativamente menor del grupo losartán en comparación con el grupo control (p = 0,01) e hidrocortisona (p = 0,01). En los demás grupos no hubo diferencias significativas. CONCLUSIÓN: La cicatrización del músculo estriado esquelético produjo menos tejido cicatricial fibroso cuando fue expuesto a losartán que cuando fue comparado con el grupo control o el grupo hidrocortisona. Nivel de Evidencia I; Estudio doble ciego aleatorio controlado por placebo.

comparative study of the management of stage 2 hypertension by combined therapy with losartan, amlodipine and hydrochlorothiazide

The most effective and accurate treatment of hypertensive patients reduces cardiovascular events and improves the quality of life. This study compared the efficacy and safety of combined [combination therapy] with an angiotensin-receptor blocker [ARB] a calcium-channel blocker [CCB] [Losartan / Amloidipine 50/10mg] vs maximal combination doses of ARB with hydrochlorothiazide [Losartan /HCTZ 100/25 mg] and maximal combination doses of CCB with HCTZ [Amlodipine /HCTZ 10/25 mg] in the management of stage 2 hypertension. This randomized clinical trial [RTC] comprised 478 hypertensive patients with mean age 50.5 +/- 5.21 years, and took place between January 2010 and December 2011 in Vasei Hospital clinic in Sabzevar. Antihypertensive drugs were washed out after 5 days of discontinuation of drugs and the patients with mean blood pressure in sitting position >/= 160 and <200 mmHg in systole and >/= 100 and <110 mmHg in diastole were randomized into three groups: Losartan / Amlodipine 50/10 mg [n =164], Losartan / HCTZ 100/25 mg [n =155] and Amlodipine / HCTZ 10/25 mg [n =159]. The end point was reaching the blood pressure below 140/90 within 56 days of treatment in each group. There was a significant difference in systolic blood pressure reductions between treatment groups [P<0.001] and also there was a significant difference between groups in reducing diastolic blood pressure [P<0.01]. The highest systolic and diastolic blood pressure reduction respectively was found in Amlodipine/losartane and losartane/HTCZ group. The ANCOVA analysis revealed that only treatment regimen had a significant effect [P=0.01] and other factor including Age, Gender, Diabetes Mellitus, Smoking and High serum cholesterol didn't have significant effect on blood pressure reduction. ARB/CCB combination therapy reduced blood pressure more effectively than the maximal doses of ARB or CCB with HCTZ in stage 2 hypertensive patients within this period of study

Efeito a curto prazo do losartan comparado ao enalapril na função ventricular esquerda e na capacidade de pacientes com insuficiência aórtica crônica grave oligo grave ou assintomáticos / Effect in short term of losartan compared with the enalapril in the left ventricular function and the physical capacity of patients with asymptomatic or minimally symptomatic chronic severe aortic regurgitation

Objetivo: analisar o efeito a curto prazo do lasartan comparado ao enalapril sobre a função ventricular esquerda em pacientes com insuficiência valvar aórtica grave, oligo ou assintomáticos, testar a segurança do lasartan nessas condições e estudar o impacto destas drogas sobre a capacidade física. Métodos: Dez pacientes com insuficiência valvar aórtica (IAo)crônica grave e com função ventricular esquerda preservada (fração de ejeção menor ou igual 0,55), foram estudados de forma prospectiva em um estudo de intervenção medicamentosa cross-over, comparando-se duas drogas: losartan e o enalapril, através de avaliação clínico-laboratorial, ecocardiograma de repouso e teste cardiopulmonar em três momentos diferentes: sem medicação, em uso de losartan, em uso de enalapril. Resultados: Foram estudados 7 (70 por cento homens e 3 (30 por cento) mulheres com idade entre 15 e 41 anos (média de 26 anos). A dose média diária de enalapril foi de 38mg com tempo médio de 3,9 meses e a de losartan foi de 90mg com tempo médio de três meses. Não houve efeitos adversos graves....

The relationship between heart rate reserve and oxygen uptake reserve in heart failure patients on optimized and non-optimized beta-blocker therapy

BACKGROUND: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test. METHODS: A total of 27 sedentary heart failure patients (86 percent male, 50±12 years) on optimized beta-blocker therapy with a left ventricle ejection fraction of 33±8 percent and 35 sedentary non-optimized heart failure patients (75 percent male, 47±10 years) with a left ventricle ejection fraction of 30±10 percent underwent the treadmill cardiopulmonary exercise test (Naughton protocol). Resting and peak effort values of both the percentage of oxygen consumption reserve and percentage of heart rate reserve were, by definition, 0 and 100, respectively. RESULTS: The heart rate slope for the non-optimized group was derived from the points 0.949±0.088 (0 intercept) and 1.055±0.128 (1 intercept), p<0.0001. The heart rate slope for the optimized group was derived from the points 1.026±0.108 (0 intercept) and 1.012±0.108 (1 intercept), p=0.47. Regression linear plots for the heart rate slope for each patient in the non-optimized and optimized groups revealed a slope of 0.986 (almost perfect) for the optimized group, but the regression analysis for the non-optimized group was 0.030 (far from perfect, which occurs at 1). CONCLUSION: The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in patients on optimized beta-blocker therapy was reliable, but this relationship was unreliable in non-optimized heart failure patients.

Comparison of Losartan and Amlodipine in hypertensive type-II diabetic patients

The present study assesses whether Losartan and Amlodipine, alone or in combination, prevent microalbuminuria in hypertensive type II diabetic patients. Department of pharmacology, Basic Medical Sciences Institute [BMSI], Jinnah Post Graduate Medical Centre, Karachi from June 2006 to January 2007. In this study 60 hypertensive diabetic patients were divided into 3 groups having 20 each. Group 'N' patients were kept as control, group 'A' patients were treated with Losartan, 50 mg once daily, group 'B' with Amlodipine 10 mg once daily and Group 'C' patients were given a combination of both the drugs i.e. tab losartan and tab amlodipine. Tablet Glibenclamide 5 mg was given according to the glicemic control. Although all the three groups showed a comparable effect in lowering both the systolic and diastolic blood pressure but the effect on proteinuria was variable. Losartan treated patients in Group 'A' shows marked reduction of proteinuria but non-significant change in creatinine clearance. In Group 'B' the patients who were treated with Amlodipine showed significant reduction in creatinine clearance, but non-significant change in proteinuria and Group 'C' patients showed countable reduction in proteinuria but a non-significant increase was observed in creatinine clearance. The results suggest that in hypertensive type II diabetic patients Losartan is worthwhile reducing both systolic and diastolic blood pressure and proteinuria significantly

Expression of NAD(P)H Oxidase Subunits and Their Contribution to Cardiovascular Damage in Aldosterone/Salt-Induced Hypertensive Rat

NAD(P)H oxidase plays an important role in hypertension and its complication in aldosterone-salt rat. We questioned whether NAD(P)H oxidase subunit expression and activity are modulated by aldosterone and whether this is associated with target- organ damage. Rats were infused with aldosterone (0.75 microgram/hr/day) for 6 weeks and were given 0.9% NaCl+/-losartan (30 mg/kg/day), spironolactone (200 mg/kg/ day), and apocynin (1.5 mM/L). Aldosterone-salt hypertension was prevented completely by spironolactone and modestly by losartan and apocynin. Aldosterone increased aortic NAD(P)H oxidase activity by 34% and spironolactone and losartan inhibited the activity. Aortic expression of the subunits p47(phox), gp91(phox), and p22(phox) increased in aldosterone-infused rats by 5.5, 4.7, and 3.2-fold, respectively, which was decreased completely by spironolactone and partially by losartan and apocynin. Therefore, the increased expression of NAD(P)H oxidase may contribute to cardiovascular damage in aldosterone-salt hypertension through the increased expression of each subunit.

Papel del sistema renina angiotensina en la respuesta simpática inducida por la prueba presora al frío en humanos / Role of the renin-angiotensin system on the sympathetic response induced by the cold pressor test in humans

El objetivo del presente estudio fue evaluar el papel del receptor AT1 de la angiotensina sobre la respuesta simpática inducida por la prueba presora al frío (PPF), en voluntarios sanos. Se incluyeron 82 sujetos sanos, en un estudio doble ciego controlado con placebo. Se determinaron los valores de la presión arterial y la frecuencia cardiaca, antes y 175 minutos después de la administración oral única de placebo, losartan (59 mg), valsartan (80 mg) o eprosartan (600 mg). Inmediatamente después, los sujetos fueron sometidos a la prueba presora al frío (PPF), midiéndose los mismos parámetros hemodinámicos. La PPF incrementó la presión arterial sistólica, diastólica y media así como la frecuencia cardíaca en el grupo placebo. El pretratamiento con losartan, valsartan o eprosartan bloqueó la respuesta presora a la PPF sin producir cambios en la respuesta de frecuencia cardiaca. Nuestros resultados demuestran que la angiotensina II endógena, a través del receptor AT1, contribuye a la respuesta al estrés mediada simpáticamente en humanos.

Perfil do tratamento da insuficiência cardíaca na era dos betabloqueadores / Heart failure treatment profile at the beta blockers era

OBJETIVOS: A inibição dos sistemas renina-angiotensina-aldosterona (SRAA) e sistema nervoso autônomo simpático aumentou a perspectiva de sobrevida desses pacientes, além de permitir substancial melhora na qualidade de vida. O objetivo deste trabalho foi avaliar a realidade do tratamento aplicado e seu impacto sobre a doença em pacientes acompanhados em um ambulatório especializado em insuficiência cardíaca(IC). MÉTODOS: Foram estudados 96 pacientes acompanhados no ambulatório de Insuficiência Cardíaca e Transplante do Instituto do Coração, do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Os dados foram coletados durante a consulta ambulatorial a partir de prontuário médico e exame clínico. A escolha dos pacientes foi aleatória. RESULTADOS: A maior parte dos pacientes encontrava-se em classe funcional II (42,3 por cento) e em estágio C de evolução (94,9 por cento). A prescrição médica para os pacientes foi bastante próxima do preconizado pelas diretrizes. Aproximadamente 95 por cento recebem inibidores do SRAA (inibidor de ECA - enalapril e captopril - ou antagonista dos receptores de angiotensina-losartan), enquanto 85 por cento dos pacientes recebem, além desses, agentes betabloqueadores (carvedilol). A dose média prescrita também se aproxima das utilizadas nos grandes estudos, e atinge mais de 60 por cento da dose máxima de cada medicação. Os dados hemodinâmicos encontrados mostram pacientes estáveis, apesar da intensidade da disfunção e do remodelamento ventricular destes. CONCLUSÃO: Pacientes portadores de IC acompanhados por equipe médica especializada têm prescrição médica mais próxima do preconizado. Esses pacientes, embora com características marcadas de gravidade da doença, conseguem estabilidade hemodinâmica e clínica com a otimização terapêutica adequada.

OBJECTIVES: The inhibition of the rennin-angiotensin-aldosterone system (RAAS) and sympathetic autonomous nervous system has increased the perspective of survival in these patients, as well as allowing the improvement of the quality of life. The aim of this study was to evaluate the reality of the treatment employed and its impact on the disease in patients followed at a specialized heart failure (HF) outpatient clinic. METHODS: A sample of 96 patients followed at the HF and Transplant Outpatient Clinic of Heart Institute of the University of São Paulo School of Medicine (InCor -HCFMUSP) were evaluated. The data were collected during the ambulatory consultation from the medical files and through physical examination. Patients were randomly selected for the study. RESULTS: Most of the patients were Functional Class II (42.3 percent) and evolution stage C (94.9 percent). The medical prescription given to the patients was quite similar to the one recommended by the directives. Approximately 95 percent of them received RAAS inhibitors (ACE inhibitor - enalapril and captopril - or angiotensin receptor antagonist - losartan), whereas 85 percent of the patients additionally received beta blockers (carvedilol). The mean dose prescribed was also similar to the one used in large studies and reached more than 60 percent of the maximum dose for each medication. The hemodynamic data show that patients were stable, despite the intensity of the dysfunction and ventricular remodeling observed in these patients. CONCLUSION: Patients with HF followed by a specialized medical team receive a medical prescription that is closer to the recommended one. These patients, despite the marked characteristics of disease severity, achieve hemodynamic and clinical stability with an adequate therapeutic optimization.

Inhibitory Effect of Angiotensin Blockade on Hepatic Fibrosis in Common Bile Duct-ligated Rats / 대한간학회지

BACKGROUNDS AND AIMS: Angiotensin receptors are found on hepatic stellate cells, which participate in hepatic fibrosis. Therefore, it is presumed that angiotensin has a role in hepatic fibrosis. The aim of this study was to evaluate the effects of angiotensin blockade on inhibition of hepatic fibrosis in cirrhotic rat model. Material and METHODS: Cirrhosis with portal hypertension was produced by common bile duct ligation (BDL) in the adult Sprague-Dawley rats. They were classified into 4 groups (each group n=6) as follows; G1: BDL without drug, G2: BDL+captopril 100 mg/kg/day beginning 2 weeks after BDL, G3: BDL+captopril 100 mg/kg/day, starting just after BDL, G4: BDL+losartan 10 mg/kg/day, starting just after BDL. After 4 weeks following BDL, hepatic fibrosis was histomorphologically analyzed by Batts & Ludwig score. Alpha smooth muscle actin by immunohistochemical stain, hydroxyproline contents of liver tissue by spectrophotometry and expression of collagen, procollagen, and TGF-beta by real-time PCR were measured. RESULTS: Batts & Ludwig score were 3.8, 3.0, 2.6,and 2.6 in G1, G2, G3, and G4, respectively. The expression of alpha-SMA was significantly lower in G3 and G4 than in G1; 11.9%, 10.9%, 2.6%, and 1.1% in G1, G2, G3, and G4, respectively (p<0.05). The concentration of hydroxyproline (microgram/g liver tissue) was lower in G3 and G4 compared with G1 (p<0.05). Also, the administration of angiotensin blockade just after BDL significantly reduced the expression of collagen, procollagen, and TGF-beta mRNA. CONCLUSIONS: Angiotensin blockades are effective in the prevention of hepatic fibrosis in BDL rats.

Estudo `LOTHAR`: avaliação de eficácia e tolerabilidade da combinação fixa de anlodipino e losartana no tratamento da hipertensão arterial primária / The `LOTHAR` study: evaluation of efficacy and tolerability of the fixed combination of amlodipine and losartan in the treatment of essential hypertension

OBJETIVO: O estudo LOTHAR avaliou a eficácia, tolerabilidade e os efeitos metabólicos em médio e longo prazo (um ano) da combinação fixa de anlodipino e losartana versus anlodipino e losartana isoladamente. MÉTODOS: Estudo multicêntrico brasileiro, randomizado, duplo-cego e comparativo realizado com 198 pacientes com hipertensão arterial primária em estágios 1 e 2. RESULTADOS: A combinação fixa apresenta alta eficácia anti-hipertensiva que se mantém em longo prazo com percentual reduzido de escape do controle pressórico, inferior a dos dois regimes monoterápicos de comparação. Em longo prazo, mais de 60 por cento dos pacientes tratados com a combinação fixa permaneceram com níveis da PAD < 85 mmHg e o efeito anti-hipertensivo quando avaliado pela MAPA persistiu nas 24 horas com relação vale-pico de 76,7 por cento. A freqüência de eventos adversos foi bastante reduzida neste grupo sendo a incidência em longo prazo de edema de membros inferiores cerca de quatro vezes menor que a observada com o anlodipino isolado. A combinação fixa não alterou os metabolismos da glicose e dos lípides tanto em médio quanto em longo prazos. CONCLUSAO: Estes resultados nos permitem afirmar que a combinação de anlodipino e losartana, a primeira combinação fixa de um antagonista dos canais de cálcio e um bloqueador do receptor da angiotensina II disponível no mercado farmacêutico constitui-se em excelente opção para o tratamento da hipertensão arterial em larga gama de pacientes hipertensos.

Caracterização de eventos na fibrose túbulo-intersticial tratada com micofenolato mofetil e/ou losartan no modelo de ablação renal / The characteriation of eventss in tubuloointersticial fibrosis attenuated bby losartan and/or micopphenollate mofetil therapy in the remnant kidnney

Para caracterizar os eventos na fibrose túbulo-intersticial renal, foi realizado estudo em ratos submetidos a nefrectomia 5/6 e tratados com micofenolato mofetil e/ou losartan. Cortes histológicos de rim foram submetidos a processamento histológico e imuno-histoquímico para a identificação e quantificação do colágeno e de vários marcadores de células epiteliais, mesenquimais e inflamatórias. O estudo morfométrico foi realizado utilizando-se imagens digitalizadas e método computadorizado de análise de imagem. Verificou-se redução da deposição de colágeno e da expressão daqueles marcadores celulares, principalmente nos grupos tratados com a associação micofenolato mofetil e losartan / In order to characterize the events of tubulointerstitial fibrosis, it was performed a study in 5/6 ablation rats receiving losartan and/or micophenolate mofetil therapy. Kidney sections were submitted to several histochemical and immunohistochemical procedures. Morphometric evaluation was performed using digitalized image and a computer assisted image analyzer...

Evaluation of efficacy and tolerability of Losartan and Ramipril combination in the management of hypertensive patients with associated diabetes mellitus in India (LORD Trial).

AIM: The study was conducted to evaluate efficacy and tolerability of fixed dose combination (FDC) of Losartan and Ramipril in the management of mild to moderate hypertensive Native Asian Indian patients with associated diabetes mellitus. The secondary objective was to evaluate the efficacy of the combination in reducing microalbuminuria. MATERIAL AND METHODS: The study was an open, non-comparative, multicentric clinical trial conducted in seven Indian centres in 315 eligible patients. All the patients were treated with Losartan 50 mg + Ramipril 2.5 mg or Losartan 50 mg + Ramipril 5 mg once a day in 12 weeks and consisted of a total of eight visits. RESULTS: The mean age of patients was 52.93 years (range 45 - 60 years). Of the total patients, 62.86% were males and 37.14% were females. The mean prestudy systolic blood pressure was 160.56 +/- 14.44 which was significantly reduced to 126.85 +/- 9.78 at the end of 12 weeks (P < 0.001). Similarly the mean diastolic blood pressure was 98.91 +/- 8.33 at baseline (stage I) which was significantly reduced to 79.82 +/- 5.42 at the end of 12 weeks (P < 0.001). A mean fall of 33.72 mmHg in systolic blood pressure and the mean fall of 19.10 mmHg was observed in systolic and diastolic blood pressure respectively at the end of the treatment which was statistically highly significant (P < 0.001). The JNC-VII goal of blood pressure < 130/80 was achieved in 79.05% patients after the treatment which losartan and ramipril combination only. Microalbuminuria (urinary albumin excretion > 30 but < 300 mg/day) was seen in 83/250 (33.2%) patients and 135 (54%) patients had clinical proteinuria (albuminuria) at baseline. At the end of the therapy 20.8% patients achieved normoalbuminuria. Good to excellent efficacy response was reported in 98.09% patients and 98.41% patients reported good to excellent tolerability to the treatment. CONCLUSION: The fixed dose combination of Losartan and Ramipril showed good to excellent efficacy response in 98.10% patients and achieved a target blood pressure of 130/80 mmHg in 79.05% patients in 12 weeks. The combination reduced the urinary albumin excretion in majority of the patients with microalbuminuria and proteinuria (the major marker of nephropathy).

Efectos de la administración temprana de losartan sobre el remodelamiento ventricular en conejos con infarto de miocardio experimental / Effects of the early administration of losartan on ventricular remodeling in rabbits with experimental myocardial infarction

En el presente trabajo se evaluaron los efectos de la administración temprana de losartán (Los) sobre el remodelamiento ventricular (RV) en conejos con infarto de miocardio experimental (IM). Conejos Neozelandeses fueron sometidos a ligadura de la arteria coronaria izquierda. Se analizaron 4 grupos: operación simulada o sham (G1, n=13), IM (G2, n=13), sham+Los (G3, n=13), IM+Los (G4, n=13). Los (12.5 mg/ kg/día) comenzó a administrarse a las 3 horas post-cirugía. Los animales fueron sacrificados a los 35 días y los corazones fueron perfundidos según la técnica de Langendorff. Se determinaron curvas presión-volumen (P/V) sistólicas y diastólicas. Cuatro animales por grupo se utilizaron para análisis histológico. Los corazones fueron fijados en formol, se calculó la relación entre el peso del corazón y del animal (Pc/Pa), seguidamente fueron cortados y teñidos con tricrómico de Masson y picrosirius red. Se midió el tamaño de infarto (TIM%), el espesor del septum (ES) y de la cicatriz, mediante análisis morfométrico. Los valores se expresaron como X ±SEM. Resultados: El TIM% fue en G2=25.38±5.31% y en G4=21.85±4.13%. El Pc/Pa fue: 3.45±0.16; 3.52±0.25; 2.87±0.16 (p<0.05 vs grupos no tratados) y 3.23±0.18 en G1, G2, G3 y G4 respectivamente. El Los desplazó la relación P/V diastólica a la derecha tanto en G3 y G4 (p<0.05 vs G1 y G2) y no modificó la función sistólica. El ES fue menor en G3 y G4 (P<0.05 vs G2), y G4 presentó menor cantidad de colágeno en la cicatriz (p<0.05 vs G2). En conclusión: la administración temprana de losartán modificó desfavorablemete el RV, incrementando la dilatación y disminuyendo el colágeno y el espesor de la cicatriz.

Effect of losartan on albuminuria, peripheral and autonomic neuropathy in normotensive microalbuminuric type 2 diabetics.

BACKGROUND: Angiotensin converting enzyme (ACE) inhibitors are emerging as effective agents for preventing microvascular complications of diabetes. Losartan (angiotensin II antagonist) has an antihypertensive efficacy equivalent to ACE inhibitors, however its role in microvascular complications is not yet known. MATERIAL AND METHODS: We studied the efficacy of losartan (50 mg once daily for 12 weeks) on albuminuria, peripheral and autonomic neuropathy in 25 normotensive microalbuminuric type 2 diabetics who were asymptomatic for neuropathy. RESULTS: Mean age was 46.6 +/- 4.34 years with the average duration of diabetes being 8.1 +/- 1.54 years. Albuminuria improved significantly from 54 +/- 9.35 mg/L to 32.8 +/- 25 mg/L (Paired student's t-test, P=0.0005) after therapy. Autonomic neuropathy was observed in 64% while 76% had peripheral neuropathy; but there was no improvement with losartan. The duration of diabetes had a negative correlation with autonomic neuropathy. It also had a similar negative correlation with median and common peroneal nerve motor conduction velocities (Pearson's correlation coefficient, r = -0.53, P<0.01 and r = -0.56, P<0.01 respectively) implying that autonomic and peripheral neuropathy worsen as a diabetic ages. However, no correlation existed between albuminuria and autonomic or peripheral nerve function. CONCLUSION: Autonomic and peripheral neuropathy are highly prevalent in normotensive microalbuminuric diabetic patients. Losartan remarkably improves albuminuria but a similar benefit in autonomic or peripheral neuropathy is not seen over 12 weeks. The future may see a defining role for losartan in microvascular complications in normotensive diabetics.

An open comparative clinical trial to assess the efficacy and safety of losartan versus enalapril in mild to moderate hypertension.

OBJECTIVES: To compare the efficacy and safety of losartan with enalapril, in mild to moderate hypertension. METHODS: An open, enalapril controlled study was conducted in 30 patients with mild to moderate hypertension. Losartan 50 mg was administered to patients for eights weeks. Throughout the study blood pressure was measured every two weeks. Routine laboratory investigations were performed before entering the trial, fourth week and at the end of the study. Adverse effects were recorded. After eight weeks losartan was stopped and enalapril 10 mg daily was administered to the same patients after two weeks washout period. The same methodology that was followed for losartan trial was repeated for enalapril trial also. RESULTS: Losartan treatment resulted in a highly significant reduction in the mean sitting diastolic blood pressure. Comparison with enalapril showed that both drugs are equally efficacious in reducing blood pressure in mild to moderate hypertension. The percentage of responders was slightly more with losartan than enalapril (86.7% vs 76.7%). Adverse events reported with losartan were mild. Enalapril also was well tolerated like losartan but there was high incidence of dry cough, which was reported in nine patients (30%). CONCLUSIONS: Losartan is an effective antihypertensive drug with an excellent safety and tolerability profile. It shows similar blood pressure lowering efficacy to that of enalapril. In contrast to enalapril, losartan does not cause dry cough.

Efficacy and safety of losartan-amplodipine combination--an Indian postmarketing surveillance experience.

The present study was conducted among 719 patients enrolled by 109 doctors to evaluate the efficacy and tolerability of the combination of losartan potassium and amlodipine besylate in Indian patients with mild to moderate hypertension. Out of them 11 patients were dropped out. Of these 708 patients 643 patients received once daily dosage of the combination whereas 10 patients received 1/2 daily, 13 patients received 1 1/2 daily and 42 patients received 1 twice daily dosage of the combination. The mean SBP in the study was 172.89 +/- 19.18 mm Hg baseline. After the 10-day treatment, the mean SBP had significant reduction ie, 13.1% from basal and at the end of day 20 of the treatment, the reduction was 19.13% from the baseline which was significant. Similarly mean DBP was 105.42 +/- 10.85 mm Hg at baseline. After treatment, the mean DBP had significant reduction. After 10- day treatment, there was 12.7% reduction from the baseline and at the end of the treatment ie, after day 20, the reduction was 17.70% from basal, which was significant. Global evaluation of efficacy was done by the physicians; 93.8% of the cases had excellent to good response and 4.9% patients had fair response. Details of any adverse event reported or noted during the treatment with the combination were recorded in the appropriate section of the case record form, whether considered treatment related or not, as reported by the patients. The severity of an adverse event was graded on a 3-point scale as mild, moderate and severe. The most common side-effects reported were oedema of feet (5.08%), ankle oedema (1.98%). Remaining adverse events included some cardiovascular events such as palpitations, gastro-intestinal events such as constipation, miscellaneous events, muscular pain, weakness, generalised swelling, etc. CNS events included giddiness, headache, insomnia, etc.

A comparative evaluation of therapeutic effects of once a day dose of losartan potassium versus enalapril maleate in mild to moderate essential hypertension.

Hypertension is a major public health problem both in the developing and developed countries of the world and if untreated, can lead to various fatal complications like cerebral stroke, encephalopathy, ischaemic heart disease (IHD), renal failure and sudden cardiac death, etc. In the present study, a comparative evaluation was made between angiotensin-II receptor antagonists like losartan potassium (50 mg daily) and angiotensin converting enzyme (ACE) inhibitors like enalapril maleate (5 mg daily) in 100 patients (50 males and 50 females having 25-50 years of age) of mild to moderate essential hypertension with diastolic blood pressure (DBP) 90-109 mmHg. Both the drugs were tried as monotherapy for their clinical efficacy, safety, tolerability and adverse effect profile in this open trial. Losartan potassium lowered the DBP to <90 mmHg in 62% of the patients at the end of 8 weeks compared to 40% in the enalapril group. Percentage of side effects with losartan was 20 and 50 with enalapril. It is concluded that both the drugs are effective antihypertensive agents and cause significant and comparable fall in systolic blood pressure (SBP) and DBP in patients of mild to moderate essential hypertension. But losartan potassium has been found to be more effective with fewer side effects when compared to enalapril maleate.

Effects of Centrally Administered Losartan on Deoxycorticosterone-salt Hypertension Rats

To investigate whether brain AT1 receptor stimulation contributes as a hypertensive mechanism to deoxycorticosterone acetate (DOCA)-salt hypertension, losartan (1 mg/4l) or artificial cerebrospinal fluid (aCSF) was injected into the lateral cerebral ventricle in conscious control uninephrectomized Wistar rats or rats with DOCA-salt for 2 or 4 weeks, and mean arterial pressure (MAP) and heart rates (HR) were recorded. In rats with DOCA-salt treatment, resting MAP increased to 144 +/- 6 mmHg after 2 weeks and to 170 +/- 5 mmHg after 4 weeks versus 115- 120 mmHg in controls. In rats with 2 week DOCA-salt treatment, MAP started declining at 4 hr after intracerebroventricular (icv) injection of losartan, and significant decreases in MAP were found at 18 and 24 hr. In rats with 4 week DOCA-salt treatment, MAP was significantly decreased at 4, 18 and 24 hr. In both groups MAP decreased to that of control rats. In control rats, icv losartan had no effect on MAP and HR. Icv aCSF did not significantly change MAP and HR in either DOCA-salt hypertensive rats or control rats. Normalization of MAP after icv administration of the AT1 receptor antagonist suggests a significant role for brain AT1 receptor stimulation in the development and maintenance of hypertension in the DOCA-salt hypertensive rat model.