正己烷对卵巢颗粒细胞雌激素合成的影响及其机制

Effects of n-Hexane on the Estrogen Synthesis in Ovaries Granule Cell

目的:探讨正己烷对生殖内分泌的干扰作用及其机制。方法:48只成年雌性Wistar大鼠按体质量随机分成4组,染毒剂量分别为:0 g/m^3、3.01 g/m^3、9.03 g/m^3、27.1 g/m^3。4 h/d静式吸入染毒,每周6 d,持续6周。染毒结束后,提取卵巢颗粒细胞进行体外培养,观察不同剂量组正己烷染毒后大鼠卵巢颗粒细胞培养液中E_2的变化,实时荧光定量PCR法检测P450arom mRNA的表达水平。结果:各剂量组大鼠动情周期呈明显缩短趋势,其中高剂量组(27.1 g/m^3)大鼠动情期、动情间期明显缩短,与对照组比较,差异有统计学意义(P<0.05)。体内染毒可抑制各剂量组卵巢颗粒细胞体外分泌E_2水平,且P450arom mRNA的表达强度均低于对照组(P<0.05)。结论:正己烷具有明显的雌性生殖内分泌干扰作用,可通过影响卵巢颗粒细胞雌激素合成过程中P450arom的表达,进而干扰雌激素的合成。这可能是正己烷生殖内分泌干扰作用的重要机制之一。

Objective： To study the effects ofn-hexane on the estrogen synthesis and the expressions of P450arom mRNA, in order to explore the mechanism of female reproductive endocrine disruption of n-hexane. Methods： Adult female Wistar rats were randomly assigned to four groups based on weight. N-hexane was given absorption 4 h/d, 6 d/week for 6 weeks at doses of 0 g/m3, 3.01 g/m3, 9.03 g/m3, 27.1 g/m3. The rats were killed and the ovaries granule ceils were took out and incubated. The E2 of ovaries granule cells were measured by the ratio immunoassays. The expressions ofP45Oarom mRNA were determinated with real-time fluorescence quantitative PCR. Results： The period of estrus stages in rats of N-hexane absoltion groups decreased than that of the control, the period of estrus and metestrus decreased significantly in the 27.1 g/m3 group compared with the control. As the concentration of N-hexane was increased, E2 levels and the expression of P450arom mRNA were significantly declined （P〈0.05）. Conclusion： N-hexane has obvious female reproductive endocrine disruption. The change in the expression ofP45Oarom mRNA in the E2 synthesis of ovaries has been shown, which is considered as important mechanism of endocrine disruption.