INVESTIGADORES
MANUCHA Walter Ariel Fernando
congresos y reuniones científicas
Título:
Cytoprotective effect of losartan in renal proximal tubules (PT) from spontaneously hypertensive rats (SHR): Role of HSP70
Autor/es:
WALTER MANUCHA; VICTORIA BOCANEGRA; CELESTE RUETE; LILIANA CARRIZO; MARÍA ANGÉLICA ABUD; CLARA PONCE; PATRICIA G. VALLES
Lugar:
La Caja de los Trebejos-Potrero de los Funes San Luis - Argentina
Reunión:
Congreso; XXIV Reunión Científica Anual de la Sociedad de Biología de Cuyo IV Reunión Anual de la Sociedad Argentina de Microscopía; 2006
Institución organizadora:
Sociedad de Biología de Cuyo
Resumen:
Caveolin proteins function to recruit lipids and proteins to caveolae, for participation in intracellular trafficking of cellular components and operation in signal transduction. Caveolin 1 (cav1) is required for normal renal AT1-receptor expression. We have demonstrated cav1 and HSP70 interaction after losartan (Los) administration in SHR cortex. In the present study, we evaluated HSP70 involvement on the cytoprotective effect of Los in SHR. Methods: Four group were studied: SHR, SHRLos and WKY with/without Los. Cav1 and HSP70 were evaluated by western blot in microdissected PT, immunoflorescence (IF) of both proteins in renal cortex. Coimmunoprecipitation (CIP) of cav1/HSP70 in absence/ presence of HSP70 was performed. TUNEL, caspase 3 activity and mRNA of Bax/BcL2. NADH oxidase activity (fluorescence). Results: Los decreased BP near controls values in SHR compared to SHR+H2O associated with decreased AT1 expression. Cav1 and HSP70 were demonstrated in membrane fractions from isolated PT of SHRLos. Increased immunoreaction was shown for both proteins by IF in membranes from PT. CIP of cav1 and HSP70 was demonstrated in cortex membranes in SHRLos. Conversely, absence of HSP70 expression was shown in membrane fractions from SHR. Decreased NADH oxidase activity near controls was demonstrated in membrane fraction of SHRLos vs SHR. No differences in apoptosis induction were found among groups. From these results, the translocation of HSP70 to membrane fraction in PT after Los administration, might exert a cytoprotective effect by decreasing oxidative stress in SHR.
