邻苯二甲酸酯类对青春期雄性大鼠生殖内分泌功能的影响及其机制研究

发布时间：2018-06-25 15:38

本文选题：青春期大鼠 + 邻苯二甲酸酯类　；参考：《汕头大学》2008年硕士论文

【摘要】： 背景: 近年来,环境因素对男性生殖健康的影响越来越引起学者们的注意。邻苯二甲酸酯类是常用的塑料制品增塑剂,有很强的拟雌激素样作用,是公认的环境内分泌干扰物,不但可以干扰下丘脑-垂体-睾丸轴的平衡,而且还可以直接或(和)间接地损害精子的生成。青春期是男性生长发育的关键时期,在此期受到外界环境不良干扰可能会影响男性生殖功能和个体的生长发育。最近,有学者认为,我们所处的环境中含有多种邻苯二甲酸酯类物质,所以我们有必要评估两种或多种邻苯二甲酸酯类混合物对人类健康的影响。邻苯二甲酸二(2-乙基己基)酯和邻苯二甲酸二丁酯是世界上最常用的两种增塑剂,并且人群最常见的接触方式是经口接触污染的水或食物。因此,本研究试图探讨邻苯二甲酸二(2-乙基己基)酯和邻苯二甲酸二丁酯联合经口染毒对青春期大鼠生殖内分泌功能的影响及其机制;这些研究对阻止、延缓或减弱上述因素对人类生殖健康的损伤有重要的意义。目的: 1)研究邻苯二甲酸酯类对雄性性行为的影响及其机制。 2)探讨邻苯二甲酸酯类对睾丸、附睾组织形态及生精功能的影响,并阐明生殖内分泌功能的改变在其中的作用。 3)研究睾丸内与精子功能相关的酶类活性的改变以及睾丸内氧化-抗氧化系统的改变,进一步探讨这些改变在生殖功能损伤机制中的作用。 4)研究睾丸中铜、锌含量及铜/锌比值的变化在邻苯二甲酸酯类引起生殖损伤中的作用。材料与方法: 健康雄性SD大鼠(6周龄)56只,分笼饲养于标准动物房(22℃),自由饮食,给予规律光照(12 h:12 h)。20只健康成年雌性SD大鼠经处理后与雄鼠交配,观察雄鼠性行为学改变。将所有雄鼠随机分为4组,每组14只,将DEHP和DBP等质量溶解于玉米油中,灌胃剂量分别为0(对照组)、375、750、1500 mg/(kg.d)。于染毒2周末各组断头法处死7只大鼠。染毒第22~24天观察雄鼠性行为学的改变,染毒4周末各组断头法处死7只大鼠。每天同一时间称重,灌胃量为5ml/Kg体重。大鼠处死后收集标本,采用组织学方法分析各组睾丸曲细精管直径大小和生精上皮高度变化,流式细胞分析仪检测各组睾丸生精细胞的变化,并用放免法检测血清中睾酮和雌二醇含量的变化;采用紫外分光光度计法检测血清和睾丸匀浆液中ACP、SDH、SOD和MDA的含量变化以及染毒4周血清中NO的变化;采用石墨炉原子发光法检测睾丸组织中铜、锌含量以及铜/锌比值的变化。结果: 1.大鼠性行为学观察:在30min内,对照组和750 mg/kg.d组分别有6只大鼠完成射精,而375 mg/kg.d组和1500 mg/kg.d组分别有7只和5只大鼠完成射精。插入潜伏期在1500mg/kg.d组较对照组和375 mg/kg.d组延长(P 0.05);射精前插入次数在1500 mg/kg.d组与对照组相比差别有统计学意义(P 0.05)。 2.睾丸组织形态学改变:曲细精管直径在染毒2周750 mg/kg.d组和1500 mg/kg.d组较对照组降低,染毒4周各剂量组曲细精管直径均较对照组明显减小。染毒2、4周,生精上皮高度在375 mg/kg.d组较对照组降低(P 0.05),在750 mg/kg.d组和1500 mg/kg.d组与对照组相比降低均具有高度统计学意义(P 0.01)。 3.流式细胞仪检测生精细胞的变化:染毒2、4周,亚单倍体细胞比例在750 mg/kg.d组和1500 mg/kg.d组升高;随染毒剂量增加,1C细胞和4C比例降低,2C细胞比例升高, G0/G1期细胞比例升高,G2/M期细胞比例降低。 4.血清睾酮(T)、雌二醇(E2)和NO的变化:染毒2周,血清T含量在750 mg/kg.d组和1500 mg/kg.d组较对照组明显降低(P 0.01);血清中E2在750 mg/kg.d组和1500 mg/kg.d组较对照组明显升高(P 0.05);染毒4周,血清T和E2含量在750 mg/kg.d组和1500 mg/kg.d组与对照组相比差别均具有高度统计学意义(P 0.01);血清中NO含量在1500 mg/kg.d组较对照组升高(P 0.05)。 5.血清及睾丸匀浆中ACP、SDH、SOD和MDA活性的变化:染毒2周,血清SOD活性在1500 mg/kg.d组明显比对照组降低(P 0.05),睾丸匀浆中ACP、SOD和MDA在1500 mg/kg.d组与对照组相比差别有统计学意义(P 0.05);染毒4周,血清ACP活性在750 mg/kg.d组与对照组相比有统计学意义(P 0.05),在1500 mg/kg.d组与对照组相比有高度统计学意义(P 0.01),血清SDH活性在1500 mg/kg.d组与对照比差别有统计学意义(P 0.05)。睾丸匀浆中ACP、SDH、SOD和MDA在750 mg/kg.d组与对照组相比差别有统计学意义(P 0.05),在1500 mg/kg.d组各项指标与对照组相比差别有高度统计学意义(P 0.01)。6.睾丸组织中铜、锌及铜/锌比值的变化:染毒2周,睾丸组织中铜含量在1500 mg/kg.d组升高(P 0.05),锌的含量和铜/锌比值较对照组差别明显(P 0.05);染毒4周,在1500 mg/kg.d组睾丸组织中锌含量明显降低(P 0.05),铜/锌比值明显升高(P 0.05)。结论: 1.邻苯二甲酸酯类可以引起雄性大鼠性行为的异常,其机制可能与体内性激素水平紊乱和NO水平变化有关。 2.邻苯二甲酸酯类对睾丸组织形态结构有严重影响,破坏睾丸生精上皮结构的完整性,干扰生精过程。 3.生精相关酶活性的改变和睾丸内氧化抗氧化系统失衡可能在邻苯二甲酸酯类引起生精功能障碍的过程中发挥了重要的作用,并且可能解释邻苯二甲酸酯类引起睾丸损伤的某些机制。 4.睾丸内铜、锌含量和铜/锌比值的变化可能与邻苯二甲酸酯类引起睾丸损伤有密切关系。
[Abstract]:Background:
In recent years, the effects of environmental factors on male reproductive health have attracted more and more attention from scholars. Phthalic acid esters are commonly used plastic plasticizers. They have strong estrogen like effects. It is a recognized environmental endocrine disruptor. It can not only interfere with the balance of the hypothalamus pituitary - testicular axis, but also direct or (and). Earthing damage sperm production. Puberty is a critical period for male growth and development. Adverse environmental disturbance may affect male reproductive function and individual growth and development during this period. Recently, some scholars believe that we are in the environment containing a variety of phthalate two formates, so we need to assess two or more kinds. The effects of phthalic acid esters on human health. Phthalic acid two (2- ethyl hexyl) ester and dibutyl phthalate are the two most commonly used plasticizers in the world, and the most common contact mode in the population is water or food contaminated by oral contact. Therefore, this study attempts to explore the two (2- ethyl hexyl) of phthalic acid two formate. The effects and mechanisms of ester and dibutyl phthalate on reproductive endocrine function of puberty rats, which are important to prevent, delay or weaken the damage of human reproductive health.
Objective:
1) to study the effects of o-benzoic acid two esters on male sexual behavior and its mechanism.
2) to explore the effects of o-phthalic acid two esters on testis, epididymis morphology and spermatogenesis, and elucidate the role of reproductive endocrine function in the process.
3) study the changes in the activity of the enzymes related to the spermatozoon function in the testis and the changes in the oxidation antioxidant system in the testis, and further explore the role of these changes in the mechanism of reproductive function damage.
4) to study the effects of copper, zinc content and copper / zinc ratio on the reproductive damage induced by o-benzoic acid two esters.
Materials and methods:
56 healthy male SD rats (6 weeks old) were kept in a standard animal room (22 degrees C), free diet, and regular light (12 h:12 h) were given to male adult female SD rats to mate with male rats after treatment. The male rats were divided into 4 groups randomly, 14 rats in each group were dissolved in corn oil, and the quality of DEHP and DBP was dissolved in corn oil and irrigation. The dosage of the stomach was 0 (control group) and 3757501500 mg/ (kg.d). 7 rats were killed at the end of the 2 weekend. The sex behavior changes of male rats were observed on day 22~24, and 7 rats were killed at the end of the 4 weekend. The weight of the rats was weighed at the same time every day and the amount of gavage was 5ml/Kg. The specimens were collected and the histology method was used after the rats were killed. The changes in testicular spermatogenic cells were detected by flow cytometry, and the changes in serum testosterone and estradiol were detected by flow cytometry. The changes in the content of ACP, SDH, SOD and MDA in serum and testicular homogenate were detected by ultraviolet spectrophotometer. The changes of NO in serum were observed for 4 weeks. The changes of copper, zinc and copper / zinc ratio in testicular tissue were detected by graphite furnace atomic fluorescence spectrometry.
Result:
1. rat sexology observation: in 30min, 6 rats in the control group and the 750 mg/kg.d group had ejaculation, while 7 and 5 rats in the 375 mg/kg.d group and 1500 mg/kg.d group completed ejaculation. The insertion latency was prolonged in the 1500mg/kg.d group compared with the control group and the 375 mg/kg.d group (P 0.05), and the number of pre ejaculatory insertion was in the 1500 mg/kg.d group and the control group. The difference was statistically significant (P 0.05).
2. the morphological changes of the testis: the diameter of the convoluted tubule was lower in the 750 mg/kg.d group and the 1500 mg/kg.d group than the control group. The diameter of the seminiferous tubule of the group was significantly lower than the control group for 4 weeks. The height of the spermatogenic epithelium was lower in the 375 mg/kg.d group than the control group (P 0.05), and in the 750 mg/kg.d group and the 1500 mg/kg.d group and the control group. The decrease was statistically significant (P 0.01).
3. flow cytometry was used to detect the changes in spermatogenic cells: the proportion of the haploid cells in the 750 mg/kg.d group and the 1500 mg/kg.d group was increased in 2,4 weeks. With the increase of the dose, the proportion of 1C cells and 4C decreased, the proportion of 2C cells increased, the proportion of G0/G1 phase cells increased, and the proportion of the cells in G2/M phase decreased.
4. the changes of serum testosterone (T), estradiol (E2) and NO: the content of serum T decreased significantly in the 750 mg/kg.d and 1500 mg/kg.d groups (P 0.01), and the serum E2 in the 750 mg/kg.d group and 1500 mg/kg.d group was significantly higher than the control group (P 0.05), and for 4 weeks, the serum T and 1500 concentrations were compared with the control group and the 750 group and the control group. The difference was statistically significant (P 0.01), and the serum NO level was higher in the 1500 mg/kg.d group than in the control group (P 0.05).
5. changes in the activity of ACP, SDH, SOD and MDA in serum and testicular homogenate: the activity of serum SOD in the 1500 mg/kg.d group was significantly lower than that in the control group (P 0.05), ACP in the homogenate of the testis, SOD and MDA in the 1500 mg/kg.d group was significantly different from the control group (P 0.05). The activity of serum albumin in the 750 group was compared with the control group for 4 weeks. Statistical significance (P 0.05), in the 1500 mg/kg.d group, compared with the control group, there was a significant statistical significance (P 0.01), and the serum SDH activity in the 1500 mg/kg.d group was significantly different from the control ratio (P 0.05). The comparison of ACP, SDH, SOD and MDA in the 750 mg/kg.d group in the testicular homogenate was statistically significant (P 0.05), in the 1500 group of fingers. Compared with the control group, there was a significant difference in statistical significance (P 0.01) the changes in copper, zinc and copper / zinc ratio in.6. testis tissue: the copper content in the testicular tissue was increased in the 1500 mg/kg.d group (P 0.05), the content of zinc and the ratio of copper / zinc were significantly different from those of the control group (P 0.05), and the zinc content in the 1500 mg/kg.d group was significantly higher than that of the control group for 4 weeks. The ratio of copper / zinc was significantly increased (P 0.05) and the ratio of copper / zinc was significantly increased (P 0.05).
Conclusion:
1. o-phthalate two formic acid esters can induce abnormal sexual behavior in male rats, which may be related to the disturbance of sex hormone levels and the change of NO level.
2. o-phthalic acid two formic acid has a serious effect on the morphology and structure of testicular tissue, which destroys the integrity of testicular spermatogenic epithelium and interferes with spermatogenesis.
The changes in the activity of 3. spermatogonia related enzymes and the imbalance of the oxidation antioxidant system in the testis may play an important role in the process of spermatogenic dysfunction induced by phthalate esters, and may explain some mechanisms of testis damage caused by phthalate esters.
4. the change of copper, zinc content and copper / zinc ratio in testes may be closely related to the damage of testicular injury caused by o-benzoic acid two formic acid ester.
【学位授予单位】：汕头大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R363

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