Action of Trivalent Chromium on Rat Liver Structure. Histometric and Haematological Studies / Accion Del Cromo Trivalente Sobre Las Estructuras Hepaticas de Ratas. Estudios Histometrico y Hematologico‪.‬

SILVA, R. F.; LOPES, R. A.; SALA, M. A.; VINHA, D.; REGALO, S. C. H.; SOUZA, A. M. & GREGORIO, Z. M. O. Action of trivalent chromium on rat liver structure. Histometric and hematological studies. Int. J. Morphol., 24(2):197-203, 2006. SUMMARY: The trace mineral trivalent chromium ([Cr.sup.3+]) is an essential nutrient involved in the regulation of carbohydrate, lipid and protein metabolism via an enhancement of insulin action. The present work had as objective to characterize histopathologically and histometrically the hepatic alterations of female Wistar rats, determined by the chromium III administration in drinking water. Adult rats received ration and drinking water ad libitum containing 300 or 500 mg/l chromium III during 4 months. Control animals received only water and ration. All animals were sacrificed by lethal dose of anesthetic. Samples of liver were fixed in 10% formalin for 24 h. Tissues for microscopical pathology were processed using standard procedures. Paraffin sections prepared at 6 [micro]m were stained with haematoxylin and eosin and PAS. Besides the histopathological exam, histometrical techniques were used. The blood was collected and processed for hematological study. Histopathological analysis revealed periportal, midzonal and pericentrilobular zones with parenchyma cells with varying degrees of vacuolation. Many hepatocytes are ballooned and the nuclei were in lysis. The centrilobular vein was dilated and congested. Dilated sinusoids containing erythrocytes were observed. The portal area showed fibrosis, biliar duct proliferation with small cells. Histometric study showed increased cytoplasm and cell volumes, and small values for number of hepatocytes per [mm.sup.3]. Lymphopenia was observed in 500 mg/l [Cr.sup.3+]/l treated animals. These results indicate that the chromium III has a direct participation in liver structures alterations.