Evolution of organic anions renal excretion in rats with bilateral ureteral obstruction (B).

VILLAR, SILVINA RAQUEL; BRANDONI, ANABEL; TORRES, ADRIANA M¨®NICA

Buenos Aires.

Congreso; XXXIX Reuni¨®n anual de la sociedad Argentina de farmacolog¨ªa experimental.; 2007

Sociedad Argentina de Farmacolog¨ªa Experimental (SAFE)

EVOLUTION OF ORGANIC ANIONS RENAL EXCRETION IN RATS WITH BILATERAL URETERAL OBSTRUCTION (B). Villar S., Brandoni A., Torres AM. Farmacolog¨ªa. Fac Cs Bioq y Farm. UNR. CONICET. Rosario. E-mail: admotorres@yahoo.com.ar.   The organic anion transporters play an important role in renal elimination of anion drugs, including ¦Â-lactam antibiotics, cytostatic agents, diuretics and antiviral drugs. The aim of the present study was to evaluate the evolution of p-aminohippurate (PAH) renal excretion and cortical renal expression of the organic anion transporters (OAT1 and OAT3) in rats with B. Both ureters were ligated during 24 h, then they were released and the studies were done after 1 (B1,n=5), 2 (B2,n=6) and 7 days (B7,n=5). A parallel group of sham rats (S,n=16) was employed. PAH renal clearance (Cl, mL/min/100g b.w.) was determined employing conventional techniques, and OAT1 and OAT3 expression using immunoblotting and immunohistochemical techniques. Data were analysed with ANOVA and Newman-Keuls P<0.05: [a]vsS, [b]vsB1, [c]vsB2, [d]vsB7. B1 and B2 rats showed a clearance of PAH lower than S (S: 3.77¡À0.41; B1: 0.49¡À0.18 a,d; B2: 0.83¡À 0.18 a,d; B7: 2.79¡À0.23 b,c). Immunoblotting revealed significant decreases in both OAT1 and OAT3 expression in basolateral plasma membranes in B1 and B2. The expression of OAT1 and OAT3 recovered to control level in B7. Immunohistochemical assays confirmed these results. These data demonstrate that modifications in OAT1 and OAT3 expression could explain the evolution of organic anions renal excretion in rats with B.