氟中毒对小鼠下丘脑—垂体—睾丸轴结构及生殖相关基因的影响

发布时间：2018-07-11 19:05

本文选题：氟中毒 + 小鼠　；参考：《山西农业大学》2015年硕士论文

【摘要】：[目的]多年来对氟的研究表明,适量的氟有利于维持钙磷正常代谢,预防龋齿,而过量的氟可导致多种组织器官的损伤,引起氟中毒。氟对雄性生殖系统的影响是多方面的,而氟对生殖内分泌方面的研究还较少。本文主要通过real-time PCR、组织切片、透射电镜等技术,结合血清中生殖相关激素的含量、骨氟含量、精子畸形率等的变化,综合分析氟暴露对小鼠下丘脑-垂体-睾丸轴的影响,并进一步探讨其对生殖系统损伤的分子机制。[方法]48只8周龄性成熟雄性昆明小鼠,随机分为四组：对照组、低氟组、中氟组、高氟组,对照组给予去离子水,氟处理组分别给予含25、50、100mg/LNaF的去离子水,饲喂60天。饲养过程中记录生长状况,并定期记录体重。染毒结束后,采集血清、精子和下丘脑、垂体、睾丸、股骨等组织,进行相关的指标测定,包括使用氟离子选择电极测量骨氟含量,使用放射免疫法测量血清中生殖相关激素的含量,使用HE染色和透射电子显微镜观察组织形态结构的变化,使用real-time PCR检测生殖相关基因mRNA的表达等。[结果]①与对照组相比,各氟处理组骨氟含量明显升高,在中氟组和高氟组差异显著(p0.001)；而体重、体增重、主要脏器系数均无显著性差异(p0.05)。②精子畸形率在各氟处理组明显升高,与对照组相比,在高氟组差异显著(p0.01)；而血清中卵泡刺激素(FSH)、黄体生成素(LH)、睾酮(T)激素含量与对照组相比无显著性差异(p0.05)。③通过制作病理组织切片,HE染色后观察发现,下丘脑和垂体组织无明显的病理变化,而睾丸组织在氟处理组出现了不同程度的损伤,高氟组尤为明显,出现了管腔中成熟精子明显减少,各级生精细胞排列紊乱,层数减少,生精小管周围间隙变宽,间质细胞出现了空泡。④透射电镜结果显示,下丘脑神经元细胞核染色质异常聚集,核膜肿胀,线粒体嵴断裂,神经髓鞘板层离散,呈葱皮样变；垂体中促性腺激素细胞染色质聚集,线粒体肿胀、空泡化,内质网扩张；睾丸组织中精原细胞、精母细胞、支持细胞染色质浓缩,线粒体空泡化,精子细胞顶体膜破裂,间质细胞核破裂,线粒体空泡化严重。⑤Real-time PCR检测结果显示,与对照组相比,下丘脑和垂体中的生殖相关激素的基因mRNA表达量无显著差异(p0.05),而睾丸组织中的FSHR、LHR、INHα、INHβB和SHBG基因mRNA表达量都明显下降,其中FSHR表达量只在高氟组差异显著(p0.05),LHR、INHα和SHBG表达量在中氟组和高氟组差异显著(p0.05),而INHβB表达量在低、中、高氟组均差异显著(p0.05)。[结论]本次试验结果表明,60天氟暴露主要对睾丸的形态结构和生殖相关的基因产生了影响,而通过血脑屏障对下丘脑和垂体产生的影响是其次的。
[Abstract]:[objective] the study on fluoride for many years showed that the proper amount of fluoride is beneficial to maintain the normal metabolism of calcium and phosphorus and prevent dental caries, and excessive fluoride can lead to the injury of various tissues and organs and lead to fluorosis. The effects of fluorine on male reproductive system are various, but there are few studies on reproductive endocrine. The effects of fluoride exposure on hypothalamus-pituitary-testicular axis in mice were analyzed by means of real-time, tissue section, transmission electron microscopy and the changes of serum reproductive hormones, bone fluorine content and sperm deformity rate. Furthermore, the molecular mechanism of its damage to reproductive system was discussed. [methods] Forty-eight 8-week-old male Kunming mice were randomly divided into four groups: control group, low fluorine group, middle fluorine group, high fluoride group, control group, deionized water, fluorine treatment group, and deionized water containing 2550 mg / L NAF for 60 days. During feeding, the growth status was recorded and the weight was recorded regularly. After the exposure, serum, sperm, hypothalamus, pituitary, testis, femur and other tissues were collected, and related indexes were measured, including the use of fluorine ion selective electrode to measure the fluorine content in bone. The contents of reproductive related hormones in serum were measured by radioimmunoassay, the morphological changes of tissues were observed by HE staining and transmission electron microscope, and the expression of reproductive related genes was detected by real-time PCR. [results] 1Compared with the control group, the bone fluorine content in each fluorine treatment group was significantly higher than that in the middle fluorine group and the high fluorine group (p0.001), while the weight, body weight, weight gain, There was no significant difference in the main organ coefficients (p0.05) .2 the sperm deformity rate was significantly higher in each fluorine treatment group than in the control group (p0.01). However, the levels of FSH, LH and T in serum were not significantly different from those in the control group (p0.05). The results showed that there were no obvious pathological changes in hypothalamus and pituitary after HE staining. However, testicular tissue was damaged in different degrees in fluoride treatment group, especially in high fluoride group, in which mature spermatozoa decreased obviously, spermatogenic cells of all levels were arranged in disorder, the number of layers decreased, and the space around seminiferous tubules became wider. The results of transmission electron microscope showed that hypothalamic neurons showed abnormal aggregation of nuclear chromatin, swelling of nuclear membrane, rupture of mitochondrial ridge, scattered lamellar layer of nerve myelin, and scallion dermatosis. Pituitary gonadotropin cell chromatin aggregation, mitochondria swelling, vacuolation, endoplasmic reticulum dilatation; testicular tissue spermatogonium, spermatocyte, Sertoli cell chromatin concentration, mitochondrial vacuolation, sperm cell acrosome membrane rupture, When the interstitial nucleus was ruptured and the mitochondria vacuolated seriously, the results of .5Real-time PCR showed that, compared with the control group, There was no significant difference in mRNA expression of reproductive hormone between hypothalamus and pituitary (p0.05), while the mRNA expression of FSHR-LHR-INH 伪 -INH 尾 B and SHBG in testicular tissue decreased significantly. The expression of FSHR was significantly different only in the high fluorine group (p0.05) and in the middle fluorine group and the high fluorine group (p0.05), while the expression of INH 尾 B was lower in the middle fluorine group than in the high fluoride group (p0.05). [conclusion] the results showed that 60 days of fluoride exposure mainly affected the morphological structure and reproductive genes of testis, while the effect of blood-brain barrier on hypothalamus and pituitary was the second.
【学位授予单位】：山西农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X503.22

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