RESUMEN
<p><b>OBJECTIVE</b>To investigate the effect of potassium iodide on the expression of nuclear factor-kappaB and fibronectin.</p><p><b>METHODS</b>The experiment was performed with 72 SD rats weighing about 180-220 g. The animals were randomly assigned into nine groups. Group A, B, C (n=8) served as control and were fed with distilled water for 1 month, 2 month, 3 month respectively. Group D, E, F (n=8) served as lead exposed and were fed with water with 0.5% lead acetate for 1 month, 2 month, 3 month respectively. Group G, H, I (n=8) served as potassium iodide and lead exposed and were treated with 0.5% lead acetate simultaneously taking potassium iodide 3 mg/100 g weight by intragastric administration for 1 month, 2 month, 3 month respectively. Animals of different groups were sacrificed at the end of the treatment. Ultrastructure of kidney was observed by electron microscopy; Expression of NF-kappaB and FN protein and mRNA in kidney were measured respectively by immunohistochemistry and RT-PCR.</p><p><b>RESULTS</b>Electron microscopic examination revealed potassium iodide could restrain the denaturalization in epithelial cells and mitochondrial cristae. The expressions of NF-kappaB protein (0.2315 +/- 0.0624, 0.3213 +/- 0.0740, 0.4729 +/- 0.0839) and mRNA (0.4370 +/- 0.0841, 0.5465 +/- 0.0503, 0.6443 +/- 0.0538) in all the lead exposed groups continuously increased compared with correspondent control groups; Group I was decreased obviously compared with group F. The expressions of FN protein (0.4243 +/- 0.0595, 0.4917 +/- 0.0891) and mRNA (0.8650 +/- 0.0880, 0.8714 +/- 0.0980) in group E and F increased compared with group B and C, but the expressions of FN protein in group I significantly decreased compared with group F; The expressions of FN mRNA in Group H and I significantly decreased compared with group E and F.</p><p><b>CONCLUSION</b>The potassium iodide can ameliorate renal ultrastructure and degrade expression of nuclear factor-kappaB and fibronectin induced by lead.</p>