蒿甲醚对日本血吸虫核苷摄入和核酸含量的影响

EFFECT OF ARTEMETHER ON NUCLEOSIDE UPTAKE AND NUCLEIC ACID CONTENT IN SCHISTOSOMA JAPONICUM *

目的： 观察蒿甲醚（ Ａｒｔ） 对日本血吸虫核苷摄入和核酸含量的影响。方法： 感染小鼠１ 次灌服（ｉｇ） Ａｒｔ ３００ ｍｇ／ｋｇ 后２４ ｈ 或４８ ｈ ， 分别测定雌虫（ ♀） 、雄虫（ ♂） 的 Ｒ Ｎ Ａ 和 Ｄ Ｎ Ａ 含量。另取经 Ａｒｔ 作用２４ ｈ 后的♀及♂虫体， 作体外培养２ ｈ 或４ ｈ ， 测定虫体对３ Ｈ 腺苷、［５３ Ｈ］ 尿苷和［ 甲基３ Ｈ］ 胸苷的摄入量以及上述３ Ｈ 标记核苷摄入虫体核酸的量。结果： 经 Ａｒｔ 体内作用４８ ｈ 后， 血吸虫♀虫的 Ｒ Ｎ Ａ 和 Ｄ Ｎ Ａ 含量分别较对照组减少５１６ ％ 和２３５ ％ ， 差异均显著， 而♂虫 Ｒ Ｎ Ａ 含量减少４２４ ％ 。♀及♂虫体经 Ａｒｔ 作用后移置体外培养２ｈ 或４ ｈ ， ♀虫对３ 种３ Ｈ 标记核苷的摄入量均较对照组的明显为少， 减少率达３５２ ％ ～５０１ ％ 。体外培养２ ｈ ，［ 甲基３ Ｈ］ 胸苷掺入♀虫 Ｄ Ｎ Ａ 的量较对照组减少７１４ ％ ， 培养４ ｈ 后， ［３ Ｈ］ 腺苷掺入♀虫 Ｒ Ｎ Ａ 和 Ｄ Ｎ Ａ 的量较对照组减少６５２ ％ 与５００ ％ 。结论： Ａｒｔ 对日本血吸虫， 尤其是♀虫的核酸代谢有抑制作用。

AIM: To observe the effect of artemether (Art) on nucleoside uptake and nucleic acid content in Schistosoma japonicum . METHODS: RNA and DNA contents of both male and female worms harbored in mice treated intragastrically (ig) with Art 300 mg/kg for 24 h or 48 h were determined, respectively. After in vivo drug treatment , the schistosomes recovered were in vitro maintained in drug\|free medium containing [ 3H]adenosine, [5\| 3H] uridine or [methyl\| 3H]thymidine at a final concentration of 37 MBq/L or 74 MBq/L for 2 h or 4 h, the tritiated nucleoside uptake and incorporation into nucleic acid of schistosomes were measured. RESULTS: The RNA and DNA contents of female worms recovered from the host 48 h after dosing were markedly decreased by 51\^6% and 23\^5%, respectively,while the RNA content of male worms showed 42\^4% reduction. When the above\|mentioned schistosomes were in vitro exposed to the tritiated nucleoside for 2 h or 4 h, apparent decrease in tritiated nucleoside uptake with reduction rates of 35\^2%～50\^1% was seen in female worms. The incorporation of [methyl\| 3H]thymidine into the female worm DNA 2 h after incubation was reduced by 71\^4% while the incorporation of [ 3H]adenosine into the female worm RNA and DNA 4 h after incubation was reduced by 65\^2% and 50\^0%,respectively. CONCLUSION: Art exhibited an apparent effect on the nucleic acid metabolism in schistosomes, especially in female worms.