Paracetamol (APAP) afecta la solubilidad en Tritón X-100 de la Na+, K+ ATPasa (NKA) de corteza renal de rata

WAYLLACE, NAHUEL; MOLINAS, SARA M.; MONASTEROLO, LILIANA; ELÍAS, M. MÓNICA; TRUMPER, LAURA

Rosario. Argentina

Congreso; XXIII Reunión Anual de la Sociedad de Biología de Rosario; 2003

Sociedad de Biología de Rosario

PARACETAMOL (APAP) CHANGES THE TRITON X-100 SOLUBILITY OF Na+, K+ ATPASA (NKA) FROM RAT RENAL CORTEX. Wayllace Nahuel, Molinas Sara*, Monasterolo Liliana A., Elías Mónica* and Trumper Laura#. Farmacología Facultad de Ciencias Bioquímicas y Farmacéuticas. * IFISE-CONICET. #CIUNR NKA is an integral membrane protein composed by two subunits: a and b. The a1 subunit interacts with membrane associated cytoskeletal proteins leading to the formation of a detergent-insoluble complex. The basolateral localization of NKA is essential for the efficient Na+ reabsorption. In previous work, we described the development of acute renal failure after the administration of a toxic, non-lethal dose of APAP to male Wistar rats. In this study we analyzed the possibility that APAP could weaken the membrane anchorage of NKA. The following experimental groups used were: i) kidneys obtained from control rats (c), ii) kidneys obtained after one hour of APAP administration, 1000 mg/kg b.w., i.p. (APAP 1h), iii) idem ii) but after 16 hs of APAP administration (APAP16h). The cortex was isolated and homogenized in a buffer with 0.1% Triton X-100. After centrifugation (35000 xg, 14 min, 4°) supernatants representing the Triton-soluble (TS) were separated from pellets representing the Triton-insoluble (TI) fractions. a1 and b1 subunits were detected by Western blot in both fractions. The signal obtained for a1 subunit was referred to the sum of TS+TI. a1 % in TS was: C= 48.0 ± 0.15, APAP1h= 65.8 ± 2.7**, APAP 16h= 81.4 ± 8.1 **, ** p< 0.01. A trend to decrease b1 was observed in the TI fractions in APAP16h. These results could suggest that APAP promote the weakening of NKA anchorage to the basolateral membrane, the first step for the milocalization of the enzyme.