RESUMO
<p><b>OBJECTIVE</b>To observe the effects of astragalosides on content of rat liver microsomal cytochrome P450 (CYP450), activity of glutathione-S-transferase (GST) and dimethylhydrazine (DMH)-induced aberrant crypt foci formation in rats.</p><p><b>METHODS</b>Forty SD rats were randomly and equally divided into control group, Astragalus group, DMH group, Astragalus+DMH group. The animals were killed by off neck and the colorectal and liver tissues taken after treatment with astragalosides and dimethyl hydrazine . The colorectal tissues were stained by methylene blue, ACFs observed and counted, and liver microsomes isolated by differential centrifugation. The total enzyme content was detected by using differential spectrometry for carbon monoxide reduction. The glutathione (GSH) level was detected by using spectrophotometry to reflect the activity of the GST.</p><p><b>RESULTS</b>The numbers of ACF and large ACF in Astragalus+DMH group were more significantly decreased than the DMH group (P<0.05). Compared with the control group, Astragalus group and Astragalus+DMH group, CYP450 level was decreased significantly, and GST activity increased significantly in DMH group (P<0.05).</p><p><b>CONCLUSION</b>Astragalosides might reduce the number of colorectal aberrant crypt foci induced by dimethylhydrazine possibly by reducing the content of hepatic CYP450 and increasing GST activity in rats.</p>