To compare the toxic effects of glycosides of Leigongteng（Tripterygium wilfordii）（GTW）on liver，blood and reproductive system in male rats of different ages.

Fifty-six male Sprague-Dawley（SD）rats aged 3，5 and 10 weeks and 8 months（equivalent to pre-school age，school age，adolescence and adulthood）were selected.The each age group was divided into control group and GTW group by random number table method.The GTW group was given 12.5 mg/（kg·d）［equivalent to2 mg/（kg·d）for children］GTW suspension，and the control group was given the same amount of normal saline.Seven rats in each age group were taken from the control group and GTW group at 2，4，8 and 12 weeks，respectively，and the organ indexes of liver，testis and epididymis were calculated.Blood routine indexes were detected by automatic blood cell analyzer.Liver function indexes were detected by automatic dry biochemical analyzer.The serum levels of testosterone（T），follicle stimulating hormone（FSH），luteinizing hormone（LH）and estradiol（E2）were detected by ELISA.The histopathological changes of liver，testis and epididymis were observed by HE staining.Sperm density and viability were calculated under light microscope.ImajeJ software counted the proportion of spermatogonia，spermatocytes and spermatids in the seminiferous tubules of the testis.

From the perspective of the liver system，there was no significant increase in liver index in rats of all age groups during GTW intervention.Alanine aminotransferase（ALT）and aspartate aminotransferase（AST）increased at the 4th and 8th week（P<0.05），and recovered at the 12th week.The pathological morphology of the liver showed that the degree of liver damage increases with the time of gastric lavage，and there was no significant difference between different age groups.From the perspective of the blood system，a decrease in PLT（P<0.05）appeared earliest and recovered by the 12th week.The rats aged 5 and 10 weeks showed a decrease in white blood cell（WBC）at 4th week（P<0.05）and recovered at 12th week.The decrease in hemoglobin（HB）（P<0.05）appeared the latest and all except for 3-week-old rats recovered at 12th week.From the perspective of the reproductive system，5-week-old and 8-month-old rats showed a decrease in T at the 4th week（P<0.05），followed by a decrease in T in all rats（P<0.05）.Except for 3-week-old rats，all other rats showed a decrease in sperm density in the second week（P<0.05），while 8-month-old rats showed the earliest decrease in sperm density and viability in the 4th week（P<0.05）.In the second week，8-month-old rats showed a decrease in the proportion of sperm cells at the earliest stage（P<0.05）.Pathology of the testes and epididymis both showed severe damage in 8-month-old rats.

①There was no significant difference in liver damage caused by GTW in rats of different age groups，but it worsened with medication time.②The toxicity of GTW to the blood system is manifested by inconsistent decreases in blood routine indicators，and young rats are more intolerant to blood damage caused by GTW than adult rats.③Compared to young rats，adult rats are more sensitive to the reproductive toxicity of GTW.