睾酮对大鼠再生肝细胞转录活性的影响

Effects of Testosterone on Transcriptional Activity of Regenerating Hepatocytes in Rats

以血清睾酮(testosterone,T)和核仁组织区相关嗜银蛋白(argyrophil nucleolar organiting regions,AgNORs)为指标,探讨去睾丸大鼠部分肝切除(partial hepatectomy,PH)后,外源注射睾酮对其血清睾酮水平及再生肝细胞DNA转录活性的影响.结果显示:外源睾酮可使大鼠血清睾酮水平显著升高,呈明显剂量-时间效应.除低剂量睾酮(0.5mg/kg体重)处理外,其它各组再生肝细胞AgNORs颗粒数在PH后24h均明显下降,PH后24～72h又持续升高.PH后各时期,低剂量睾酮使AgNORs数目显著高于芝麻油组;而中、高剂量睾酮(2.5mg/kg和5mg/kg体重)使AgNORs数目减少,并呈现明显剂量-效应关系.结果表明:低剂量睾酮对肝细胞的转录活性起促进作用;中、高剂量则起抑制作用,且随着睾酮浓度升高,抑制作用增强.

The effect of exogenous testosterone on testosterone level in serum and DNA transcriptional activity in regenerating hepatocytes of orchiectomized rats after partial hepatectomy （PH） was studied using testosterone level in serum and argyrophil nucleolar organiting regions （AgNORs） as index. The result showed that： exogenous testosterone could cause testosterone level in serum rising in a dose-time manner obviously, the number of AgNORs in regenerating hepatoeytes decreased at 24 h after PH and kept rising during 24-72 h after PH except low dose（0.5 mg/kg） of testosterone-treated. At every time after PH, the number of AgNORs of the group treated with low dose of testosterone was more than the sesame oil, but the medium（2.5 mg/kg） and high （5 mg/kg）dose decreased in a dose-depend manner obviously. The above results indicate that： Treated with low dose of testosterone could increase transcriptional activity in regenerating hepatoeytes, but the medium and high dose could inhibit it and the inhibition enhanced as concentration increased.