RESUMEN
During the development of cirrhosis ascites-edema, peripheral vasodilatation, hypotension and an increase of the plasma concentration of several neurohormones are frequently observed. Such complex changes in the hormonal profile hinders the assessment of the relative role of each in the pathophysiology of this disease. The purpose of this work was to evaluate in a rat model of experimental cirrhosis (phenobarbital/CCl4) the role of the renin-angiotensin system in the pre-ascitic stage of the disease using the converting enzyme inhibitor captopril. Cirrhotic rats showed diminished renal and hepatic perfusion. Compared to normal rats, glomerular filtration rate in cirrhotic rats was reduced from 0.75 +/- 0.11 to 0.42 +/- 0.06 mL/min/100 g BW, and renal plasma flow was reduced from 2.37 +/- 0.28 to 1.58 +/- 0.16 mL/min/100 g BW; the indocyanine green slope changed from -0.095 +/- 0.028 to -0.057 +/- 0.01; the plasma sodium concentration fell from 144 +/- 1.5 to 131 +/- 5.40 mEq/L (all < .05). The mean arterial pressure was not reduced in the cirrhotic rats. There was no ascites. Both the acute (25 mg i.v.) and chronic (25 mg i.p. daily plus 25 mg/L in drinking water) administration of captopril to cirrhotic rats induced an increase in glomerular filtration rate and renal plasma flow along with a steeper slope in indocyanine green decay (p < .05 for all three parameters) when compared to non-treated cirrhotic animals. No changes were observed in controls. In the balance studies, an increase in urinary volume along with a decrease in urinary osmolality was recorded in cirrhotic rats on chronic captopril treatment. In conclusion, our results show an activation of the renin-angiotensin system in these rats, as disclosed by the inhibition of the converting enzyme, as well as a possible interaction with ADH.
Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Captopril/farmacología , Cirrosis Hepática Experimental/fisiopatología , Sistema Renina-Angiotensina/fisiología , Animales , Tasa de Filtración Glomerular/efectos de los fármacos , Pruebas de Función Hepática , Masculino , Ratas , Ratas Wistar , Flujo Plasmático Renal/efectos de los fármacos , Sistema Renina-Angiotensina/efectos de los fármacos , Equilibrio Hidroelectrolítico/efectos de los fármacosRESUMEN
Ten patients with acute renal failure post-septic abortion were studied. Two groups of patients are described in terms of duration of oliguria, number of dialysis per patient and maximal concentration of BUN during the acute episode of tubular necrosis. Despite different oliguric periods, when the patients reached 500 ml of urine volume in 24 hours, the recovery of diuresis was similar in both groups as well as the decrease of BUN concentration at the end of the hemodialysis period. Functional studies were carried out, up to an average of 10.5 years after the acute episode. Mean values for inulin and para-aminohippurate clearances were 107 +/- 11.53 and 534.6 +/- 62.9 ml/min./1.73 m2 in nonoliguric patients or those with a short period of oliguria. These values are not significantly different from the mean values of Wesson for normal women. On the other hand, reductions in both clearances were present in most patients who had a long period of oliguria (GFR: 84.9 +/- 4.2 and RPF: 418.1 +/- 33.1). These results demonstrate that the duration of oliguria at the time acute renal failure occurred is the most important factor influencing the rate and extent of long-term recovery of renal function.
Asunto(s)
Aborto Séptico/complicaciones , Lesión Renal Aguda/fisiopatología , Lesión Renal Aguda/etiología , Adulto , Nitrógeno de la Urea Sanguínea , Diuresis , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Pruebas de Función Renal , Embarazo , Pronóstico , Diálisis Renal/estadística & datos numéricosRESUMEN
Ten patients with acute renal failure post-septic abortion were studied. Two groups of patients are described in terms of duration of oliguria, number of dialysis per patient and maximal concentration of BUN during the acute episode of tubular necrosis. Despite different oliguric periods, when the patients reached 500 ml of urine volume in 24 hours, the recovery of diuresis was similar in both groups as well as the decrease of BUN concentration at the end of the hemodialysis period. Functional studies were carried out, up to an average of 10.5 years after the acute episode. Mean values for inulin and para-aminohippurate clearances were 107 +/- 11.53 and 534.6 +/- 62.9 ml/min./1.73 m2 in nonoliguric patients or those with a short period of oliguria. These values are not significantly different from the mean values of Wesson for normal women. On the other hand, reductions in both clearances were present in most patients who had a long period of oliguria (GFR: 84.9 +/- 4.2 and RPF: 418.1 +/- 33.1). These results demonstrate that the duration of oliguria at the time acute renal failure occurred is the most important factor influencing the rate and extent of long-term recovery of renal function.