EXPRESIÓN DE iNOS y eNOS EN AORTA DE RATAS DEFICIENTES EN VITAMINA A

GATICA LV, ALVAREZ SM, OLIVEROS LB, GIMÉNEZ MS

Mendoza, Capital (Argentina)

Congreso; XX Reunión Anual de la Sociedad de Biología de Cuyo; 2002

Sociedad de Biología de Cuyo

We have shown an increase of oxidative parameters in serum and heart due to vitamin A deficiency. Vascular endothelium participates in the control of vascular tone through the release of nitric oxide (NO) which is sintethazed by endothelial NO synthase (eNOS). Inducible NO synthase (iNOS) expression in endotelial cells occurs under conditions of oxidative stress and inflamation. Wistar male 21-day old rats were fed during three months with vitamin A-free diet (-A) and the same diet plus 8 mg of retinol palmitate/kg of diet (+A). Thoracic aortas were homogenized in presence of protease inhibitors and proteins were measured by Biuret method. Proteins (40 mg) were loaded on 8% SDS-PAGE gel. iNOS and eNOS were identified by Western blot with specific antibodies and bands were revealed using Vectastain ABC detection kit. The expression of the enzymes increased in –A rats when compared to +A. Thus, vitamin A deficiency modifies the expression of both isoforms of NO synthase in vivo, which are implicated in the regulation of vasomotor tone.