RESUMEN
To study the chronic hepatotoxicity of Chinese medicine Zishen Yutai pill (ZYP) prepared from Polygonum multiflorum with the recommended dosage in normal Beagle dogs. Low, middle and high doses of ZYP (1.5, 3.0, 6.0 g·kg⁻¹; i.e. 3×, 6× and 12× equivalent doses) were given orally to dogs for 39 consecutive weeks. At the same time, the same volume of deionized water was used as the solvent control group, one time a day. The general condition of the animals was observed every day during the period of administration, and the blood was collected before and 13, 26, 39, 43 weeks after administration to detect the biomarkers related to the hepatotoxicity of the dog serum. 2/7, 3/7 and 2/7 animals were dissected after 13, 39, and 43 weeks of administration to observe the pathological changes of the animal organs, weigh the mass of main organs and conduct pathological examination of the liver. As compared to the solvent control group, 11 liver hepatotoxicity traditional biomarkers such as ALT, AST were found no ZYP-related changes at month 3, 6, 9 of the administration and month 1 in recovery period; There was no significant difference in liver viscera index and liver pathology. Therefore, no obvious hepatotoxicity was shown by ZYP administered up to 6.0 g·kg⁻¹ for 9 months in normal dogs at doses of 1.5, 3.0, and 6.0 g·kg⁻¹.