The Labdane Ent-3-Acetoxy-Labda-8(17), 13-Dien-15-Oic Decreases Blood Pressure In Hypertensive Rats / O Labdano Ácido Ent-3-Acetóxi-Labda-8(17), 13-Dieno-15-Óico Reduz Pressão Arterial Em Ratos Hipertensos

Abstract Background: Labdane-type diterpenes induce lower blood pressure via relaxation of vascular smooth muscle; however, there are no studies describing the effects of labdanes in hypertensive rats. Objective: The present study was designed to investigate the cardiovascular actions of the labdane-type diterpene ent-3-acetoxy-labda-8(17), 13-dien-15-oic acid (labda-15-oic acid) in two-kidney 1 clip (2K-1C) renal hypertension. Methods: Vascular reactivity experiments were performed in aortic rings isolated from 2K-1C and normotensive (2K) male Wistar rats. Nitrate/nitrite (NOx) measurement was performed in aortas by colorimetric assay. Blood pressure measurements were performed in conscious rats. Results: Labda-15-oic acid (0.1-300 µmol/l) and forskolin (0.1 nmol/l - 1 µmol/l) relaxed endothelium-intact and endothelium-denuded aortas from both 2K-1C and 2K rats. Labda-15-oic acid was more effective at inducing relaxation in endothelium-intact aortas from 2K pre-contracted with phenylephrine when compared to the endothelium-denuded ones. Forskolin was more potent than labda-15-oic acid at inducing vascular relaxation in arteries from both 2K and 2K-1C rats. Labda-15-oic acid-induced increase in NOx levels was lower in arteries from 2K-1C rats when compared to 2K rats. Intravenous administration of labda-15-oic acid (0.3-3 mg/kg) or forskolin (0.1-1 mg/kg) induced hypotension in conscious 2K-1C and 2K rats. Conclusion: The present findings show that labda-15-oic acid induces vascular relaxation and hypotension in hypertensive rats.

Resumo Fundamento: Diterpenos do tipo labdano induzem uma queda da pressão arterial por meio do relaxamento do músculo liso vascular; todavia, não há estudos que descrevam os efeitos de labdanos em ratos hipertensos. Objetivo: O presente estudo foi desenvolvido para investigar as ações cardiovasculares do labdano ácido ent-3-acetóxi-labda-8(17),13-dieno-15-óico (labda-15-óico) na hipertensão renal dois rins-1 clipe (2R-1C). Métodos: Foram feitos experimentos de reatividade vascular em anéis aórticos isolados de ratos machos 2R-1C e normotensos (2R). A medição de Nitrato/Nitrito (NOx) foi feita nas aortas por meio de ensaio colorimétrico. As medidas de pressão arterial foram feitas em ratos conscientes. Resultados: O ácido labda-15-óico (0,1 - 300 µmol/l) e a forscolina (0,1 nmol/l - 1 µmol/l) relaxaram as aortas com endotélio intacto e as aortas sem endotélio dos ratos 2R-1C e 2R. O labda-15-óico mostrou-se mais eficaz na indução do relaxamento em aortas com endotélio intacto de 2R pré-contraídas com fenilefrina em comparação àquelas sem endotélio. A forscolina mostrou-se mais potente do que o ácido labda-15-óico na indução do relaxamento vascular nas artérias tanto de ratos 2R-1C quanto de ratos 2R. O aumento dos níveis de NOx induzido pelo ácido labda-15-óico foi menor nas artérias de ratos 2R-1C em comparação a ratos 2R. A administração intravenosa de ácido labda-15-óico (0,3-3 mg/kg) ou forscolina (0,1-1 mg/kg) induziu hipertensão em ratos 2R-1C e 2R conscientes. Conclusão: Os presentes resultados mostram que o labda-15-óico induz relaxamento vascular e hipotensão em ratos hipertensos.

effect of hydroalcoholic extract of olive leaves on blood pressure in rat model of two-kidney, one-clip goldblatt hypertension

In Iran's traditional medicine, the leaves of olive tree are of value for the treatment of hypertension. This study was designed to examine the effects of hydroalcoholic extract of olive leaves in rat model of two-kidney, one-clip hypertension and to further explore whether its hypotensive activity was mediated by enhancing the basal release of endothelium-derived nitric oxide. Animals were divided into two main groups including sham-operated and renal artery-clipped ones. The latter was further divided into 5 groups of untreated rats, vehicle-treated rats, which received daily oral administrations of one ml distilled water, and extract-treated rats receiving olive leaves extract at 50, 150 or 500 mg/kg in the same volume of vehicle starting the next day after the operation. Four weeks later, mean blood pressure and heart rate were measured under anesthesia before and after the administration of NG-nitro-L-arginine methyl ester [L-NAME]. Mean arterial pressures, and right kidney and heart weights of untreated and vehicle-treated renal artery-clipped rats were significantly higher but left kidney weights were significantly lower than those of shamoperated animals. However, there was no significant difference between the heart rates of these groups. Compared to vehicle-treated renal artery-clipped rats, treatment with hydroalcoholic extracts of olive leaves at 50, 150 or 500 mg/kg/day was associated with significantly lower mean arterial pressure, right kidney and heart weights but did not affect heart rate or left kidney weights. The intravenous administration of L-NAME resulted in a significant increase in mean arterial pressure in sham-operated and extract-treated rats whereas there was no change in renal artery clipped or vehicle-treated groups. The findings of the study show that hydroalcoholic extract of olive leaves prevents the clipinduced increase in mean arterial pressure, which might be partly mediated by enhancing the basal release of nitric oxide

Autotrasplante renal en la infancia / Kidney autotransplantation in childhood

Se presenta una paciente de 8 años de edad, de sexo femenino, con hipertensión arterial severa secundaria a estenosis de la arteria renal izquierda. Los estudios complementarios revelaron buena funcionalidad del riñón afectado y por la ubicación de la estenosis se realizó cirugía de autotransplante con muy buena evolución posterior

Hipertensión arterial renovascular: experiencia en el tratamiento de 50 pacientes sucesivos / Treatment of renovascular arterial hypertension: experience in the treatment of 50 succesive patients

Se estudiaron 50 pacientes diagnosticados como hipertensos renovasculares, en un período de 26 meses, según la metodología establecida en el Instituto de Nefrología. Treinta casos presentaron estenosis de arteria renal (19 unilaterales y 11 bilaterales) de causa ateromatosa en 5, fibroplasia en 10 y por arteritis en 5 casos, respectivamente. Los otros 20 enfermos presentaron hipoplasia o atrofia renal sin sitio de estenosis de la arteria. Se emplearon 3 modalidades de tratamiento: angioplastia transluminal percutánea (ATP), quirúrgico y farmacológico. De los 12 casos con ATP exitosa (4, estenosis unilateral y 8, bilateral), se obtuvo curación o mejoría de la hipertensión en el 91 %. Se realizaron 7 nefrectomías, 5 por atrofia o hipoplasia y 2 por estenosis muy severa u oclusión arterial de causa ateroesclerótica. La curación o mejoría se logró en el 85,7 % de los casos. Con tratamiento farmacológico, el control de la presión arterial se logró en el 65,6 % de los pacientes

Hipertensao arterial renovascular e insuficiencia renal / Renovascular hypertension and kidney failure

O autor apresenta um ccaso clinico de insuficiencia renal reno-vascular que apresentou uma descompensacao aguda com uso de captopril.

Utilidad del captopril en hipertensión arterial relacionada con enfermedad renal / Usefulness of captopril in arterial hypertension related to renal disease

Se estudiaron 18 pacientes del servicio de nefrología pediátrica del Hospital General, Centro Médico "La Raza", con diagnóstico de hipertensión arterial renovascular o secundaria a daño parenquimatoso, en quienes el control de las cifras tensionales fue difícil con tratamiento combinado de varios medicamentos antihipertensivos. Se administró captopril en tres tomas durante treinta días; posteriormente las cifras tensionales disminuyeron de manera significativa, tanto para la presión sistólica como para la diastólica, lo que habla en favor del control eficaz de la hipertensión arterial con dicho farmaco, estableciéndose que el sistema renina/angiotensina/aldosterona está involucrado y que puede bloquearse con la administración de captopril

Hipertension vasculorrenal en pediatria / Removascular hypertension in pediatrics

Se presentan 15 pacientes cuya edad oscila entre 5 y 17 años con hipertensión vasculorrenal. En todos, el diagnóstico se hizo con arteriografía, habiendo sido la pielografía de poca utilidad diagnóstica. En 5 había una coartación de la aorta abdominal y 4 de éstos presentaban una estenosis renal asociada. En ellos se efectuó un "by-pass" de la aorta torácica a la aorta abdominal, asociada en 4 con un "by-pass" aortorrenal. En 2 pacientes se efectuó una nefrectomía; en 8 se realizó un "by-pass" aortorrenal por estenosis de dicha arteria; en 3 de éstos debió efectuarse simultáneamente una nefrectomía contralateral. Un paciente falleció por sepsis. Ambos pacientes con nefrectomías siguen hipertensos. De los 12 pacientes restantes, 8 se hallan normotensos, 2 mejorados y 2 sin cambios. La evolución alejada va de 1 a 15 años