用逆转录-聚合酶链反应检测+G_Z重复暴露大鼠脑组织c-fos和c-jun基因表达

Study of the expression of cfos and cjun gene in the brain of rat exposured to repeated +GZ by RTPCR

目的了解＋ＧＺ重复暴露后大鼠脑组织ｃ－ｆｏｓ和ｃ－ｊｕｎ基因表达的变化，探讨＋ＧＺ引起脑损害的分子机制，为＋ＧＺ防护研究提供实验依据。方法２４只雄性Ｗｉｓｔａｒ大鼠随机分成对照组、＋ＧＺ重复暴露后３０ｍｉｎ、６ｈ和２４ｈ四组，每组６只。对照组大鼠Ｇ值为＋１ＧＺ，实验组大鼠在动物离心机上经历了３次＋１０ＧＺ／３ｍｉｎ（两次间间隔３０ｍｉｎ）作用。分别于暴露后３０ｍｉｎ、６ｈ和２４ｈ处死大鼠取脑，提取总ＲＮＡ，用建立的反转录聚合酶链反应（ＲＴ－ＰＣＲ）定量检测方法检测大鼠脑组织ｃ－ｆｏｓ和ｃ－ｊｕｎｍＲＮＡ表达水平。结果＋ＧＺ重复暴露后３０ｍｉｎ大鼠脑组织ｃ－ｆｏｓ和ｃ－ｊｕｎｍＲＮＡ明显升高，分别是对照组的２．８倍和１．５倍，但６ｈ和２４ｈ时恢复正常。结论＋ＧＺ重复暴露可诱发大鼠脑组织ｃ－ｆｏｓ和ｃ－ｊｕｎｍＲＮＡ的表达，这种表达快速且短暂，在＋ＧＺ所致脑损害的病理过程中起一定作用。

Objective To explore the molecular mechanism of brain damage induced by repeated +GZ exposures, and to provide experimental evidence for protecting +GZ induced brain damage. Methods Twentyfour concious Wistar rats served as subjects. They were randomly divided into 4 groups, using an animal centrifuge, control rats (n=6) were exposed to +1 GZ and 3 experimental rats (n=18) were exposed to +10 GZ three times, each for 3 min with 30 min interval in between. The brains were taken 30 min, 6 h and 24 h after the last centrifuge run and total RNA was isolated by singlestep acid guanidinium thiocyanatephenolchloroform extraction method. The mRNA expression levels of cfos and cjun in rat brain were measured by quantitative reverse transcription polymerase chain reaction (RTPCR). Results The cfos and cjun mRNA expression levels in rat brains taken 30 min after repeated +GZ exposures were significantly higher than those of control group, but the differences between the levels of control group and those of experimental rat brain taken 6 h and 24 h after +GZ exposure were nonsignificant. Conclusion It is suggested that cfos and cjun mRNA expression in rat brain can be stimulated by repeated +GZ exposures and the increased expression was brief and transient. The increased expression of cfos and cjun may play a role in the pathologic course of brain damage induced by+GZ exposures.