姜黄素对砷致大鼠睾丸生精细胞凋亡的拮抗作用

目的研究姜黄素对砷致大鼠睾丸生殖细胞凋亡的拮抗作用。方法将50只健康清洁级Wistar雄性大鼠随机分为5组,分别为对照(双蒸水)组和亚砷酸钠(100 mg/L)染毒组及低、中、高剂量姜黄素(100 mg/L亚砷酸钠+25、50、100mg/kg姜黄素)干预组,每组10只。亚砷酸钠采用自由饮用方式进行染毒;姜黄素采用经口灌胃方式染毒,每周3次,连续8周。测量生精小管平均直径;测定大鼠血清睾酮浓度及睾丸生精细胞凋亡指数。结果与对照组比较,亚砷酸钠染毒组大鼠血清睾酮的水平降低,生精小管直径缩小,而睾丸生精细胞凋亡指数升高,差异有统计学意义(P0.01)。与亚砷酸钠染毒组比较,中、高剂量姜黄素干预组大鼠血清睾酮的水平升高,生精小管直径增大,而睾丸生精细胞凋亡指数下降,差异均有统计学意义(P0.05)。且随着姜黄素染毒剂量的升高,大鼠血清睾酮水平和生精小管直径均呈上升趋势,而睾丸生精细胞凋亡指数呈下降趋势。结论姜黄素对砷致大鼠睾丸生殖细胞凋亡具有拮抗作用。     

Protective role of diallyl tetrasulfide on cadmium-induced testicular damage in adult rats: a biochemical and histological study

Cadmium (Cd)-induced oxidative damage is the most serious problem that leads to reproductive system failure in both human and animals. Our previous studies indicate that diallyl tetrasulfide (DTS) from garlic has the cytoprotective and antioxidant activity against Cd-induced toxicity in vivo and in vitro. The present investigation was carried out to find the influence of DTS on peroxidative damage induced by Cd in rat testes. The Cd-exposed rat testis showed a significant (p < 0.05) decrease in testes to body weight ratio, along with a significant (p < 0.05) increase in Cd accumulation, lipid peroxidation and protein carbonyl levels. In Cd-exposed rats, we also observed a significant (p < 0.05) decrease in the activities of antioxidant (superoxide dismutase, catalase and glutathione peroxidase) and glutathione metabolizing (glutathione-S-transferase, glutathione reductase and glucose-6-phosphate dehydrogenase) enzymes as well as reduced levels of non-enzymic (reduced glutathione, ascorbate and total sulphydryl groups) antioxidants. In contrast, treatment with DTS (40 mg/kg body weight orally) significantly (p < 0.05) reduced the accumulation of Cd and lipid peroxidation markers and also significantly improved the activities of antioxidant defense system in testes. Testicular protection by DTS is further substantiated by remarkable reduction of Cd-induced pathological changes. Our study has revealed that DTS renders protection against Cd-induced testicular injury by reducing Cd-mediated oxidative damage.     

Reversibility of testicular atrophy induced by Di(2-ethylhexyl) phthalate in rats

Previous studies have shown that di(2-ethylhexyl) phthalate (DEHP) results in atrophy of testes and accessory sex organs accompanied by a decreased testicular concentration of zinc in rats. An experiment was performed to determine whether those changes in rat testes are reversible changes. Young Wistar male rats were administered 2.0 g/kg of DEHP for 14 days. At that time, one-half of the rats were killed for determination of zinc and testosterone concentrations in the testis, liver, and serum, and organ weights. The remaining rats were maintained for additional 45 days without further DEHP administration. Testicular weight of rats administered DEHP over the 14-day period was significantly less than that of the control animals, and testicular testosterone content and zinc concentrations were less than those of the control animals. At the end of the 45-day recovery phase, serum testosterone concentration returned to the control level, but testicular zinc concentration and testosterone content were still lower than those of the control animals. In addition, testicular weight of DEHP-treated rats was lower than that of the control animals and histologically, only a small number of seminiferous tubules showed spermatogenesis. These results indicate that, morphologically, DEHP-induced testicular atrophy appears to be of limited reversibility.     

Inhibition of testicular steroidogenesis in the neonatal rat following acute ethanol exposure

We have previously reported detrimental effects of in utero ethanol exposure on testicular steroidogenic enzyme activity in newborn rats. It is now reported that in utero ethanol exposure during Day 12 of gestation through birth has no apparent morphological effect on the testes of Day 1 neonatal rats. It appears that the detrimental effects of ethanol on testicular steroidogenesis can be manifested at the biochemical level in the absence of morphological effects. However, it remained unknown as to whether acute exposure to ethanol would elicit similar biochemical effects as chronic ethanol exposure on testicular steroidogenesis. To test this possibility ethanol was injected at 0, 1, or 2 g/kg intraperitoneally (IP) into rats of various postnatal ages. Plasma ethanol and testosterone levels as well as testicular 17 alpha-hydroxylase and C17,20-lyase activities were measured. The results indicate that acute exposure to ethanol significantly (p less than 0.05) inhibits the catalytic activity of testicular 17 alpha-hydroxylase in the newborn rat testis. This inhibition was specific since the activity of testicular C17,20-lyase was not affected. In conjunction with the reduction in testicular enzyme activity, plasma testosterone levels were reduced to 30% of the control levels in newborn animals receiving ethanol. In older animals, i.e., postnatal Day 20 and 40 rats, plasma testosterone levels were reduced, but not significantly, following ethanol treatment. Furthermore, testicular enzyme activity was not significantly reduced following ethanol treatment in these same older animals. These results suggest that the newborn rat testis is especially sensitive to the effects of ethanol.     

Comparative analysis of antioxidants against cadmium induced reproductive toxicity in adult male rats

Abstract

The present study was conducted to compare and evaluate the potential benefits of three different antioxidants in reversing cadmium (Cd)-induced reproductive toxicity in adult male rats. Rats (n?=?5) weighing 180?±?20?gm were divided into five groups (control, Cd, Cd?+?sulforaphane, Cd?+?vitamin E, and Cd?+?plant extract). Treated groups received CdCl₂ (0.2?mg/kg), sulforaphane (25?µg/rat), vitamin E (75?mg/kg), and plant extract (100?mg/kg) for 15 days. Blood samples and testicular tissues were obtained for estimation of testosterone, Zn, and Cd concentration and daily sperm production/efficiency of sperm production. Cadmium exposure caused a significant decrease in final body weight (p?<?0.0001). The plasma concentrations of Cd were significantly increased and Zn concentration decreased (p?<?0.0001) in the Cd group as compared to the control group. The testicular concentrations of Cd were significantly increased and Zn concentration decreased (p?<?0.0001) in the Cd group as compared to the control group. Cadmium exposure caused a significant decrease (p?<?0.0001) in plasma testosterone concentrations and daily sperm production as compared to the control group. More significant effects were observed with Cd+sulforaphane, Cd?+?vitamin E, and Cd?+?plant extract treated groups in slashing Cd-induced toxicity. Present findings suggest that Ficus religiosa and sulforaphane are more powerful antioxidants as compared to vitamin E in reversing the oxidative stress and can have a protective role against Cd induced reproductive toxicity in adult male rats. Part of the mechanism involved in this protective role seems to be associated with the antioxidant properties of these agents in reducing reproductive damage.     

Fas／FasL参与热诱导大鼠睾丸生精细胞凋亡的调控

目的：探讨睾丸局部加热致大鼠睾丸生精细胞凋亡及Fas/FasL信号通路在生精细胞凋亡调控中的作用。方法16只成年SD雄性大鼠随机均分为加热组和对照组。加热组进行大鼠睾丸43℃水浴15 min;对照组行大鼠睾丸22℃水浴15 min。24 h后进行灌流和内固定,取睾丸。制作5μm的组织切片,采用睾丸原位末端标记法（TUNEL）和免疫组化分析,检测生精细胞凋亡及 Fas 和 FasL 表达。化学发光法检测大鼠血清睾酮水平。结果加热组睾丸生精细胞凋亡率（15.8％±1.6％）较对照组（2.2％±0.5％）显著增加;加热后Fas和FasL在生精细胞和支持细胞表达水平也明显升高;对照组和加热组血清睾酮（T）水平无差异。结论睾丸局部加热诱导生精细胞凋亡,Fas和FasL系统为该凋亡过程的信号通路之一。     

人羊膜间充质干细胞改善高龄小鼠睾丸功能的实验研究

目的: 探讨人羊膜间充质干细胞（hAMSC）改善高龄雄性小鼠睾丸功能的作用。方法: 以36周龄雄性小鼠为高龄模型组,10周龄小鼠为年轻对照组。31只高龄模型组小鼠随机分为5组,分别为生理盐水对照组、1%人血清白蛋白对照组和治疗组,其中生理盐水对照组3只,其余各组每组7只。治疗组小鼠尾静脉注射hAMSC,剂量分别为3.4×10⁶细胞/kg（低剂量组）、6.7×10⁶细胞/kg（中剂量组）、1.4×10⁷细胞/kg（高剂量组）。每周注射1次,治疗4次后小鼠继续饲养,5周后取血检测小鼠血清睾酮水平;行附睾内精子的分析;免疫荧光检测睾丸组织内STEM121和CD105的表达和定位,观察睾丸组织病理学改变,检测类固醇激素生成急性调节蛋白（StAR）、17β-羟基类固醇脱氢酶（17β-HSD）的表达水平。结果: 与年轻雄鼠比较,治疗前高龄雄鼠体质量增加、睾丸体质比下降、睾周脂肪质量增加（均P<0.01）,血清睾酮水平下降（P<0.05）,精子活动率降低、正常形态精子率下降（均P<0.05）。治疗前高龄雄鼠的精子计数、睾丸组织StAR和17β-HSD蛋白表达水平与年轻雄鼠比较差异无统计学意义（均P>0.05）。hAMSC治疗后,睾丸间质区可见STEM121和CD105表达的细胞;高剂量组血清睾酮水平升高（P<0.05）;睾丸组织StAR蛋白表达无显著差异（P>0.05）,但高剂量组17β-HSD蛋白表达上调（P<0.05）。中剂量组和高剂量组睾丸组织的生精小管细胞层数较人血清白蛋白对照组增多（P<0.05）。结论: 初步实验结果表明,hAMSC对睾丸衰老具有保护作用,并促进雄激素合成。     

镉对大鼠肾小管上皮细胞E-cadherin影响

目的 探讨镉对体内肾小管上皮细胞E-cadherin依赖的黏附连接是否产生损伤作用。方法将大鼠分2组。实验组皮下注射含Cd 1．4mg／kg CdCl2溶液，每周3次，共4周。对照组在相应时间内皮下注射生理盐水。4周后，收集大鼠24螺样，切取肾皮质。测定尿碱性磷酸酶（LDH）活性、尿蛋白和肌酐含量、肾皮质谷胱甘肽（GSH）和丙二醛（MDA）含量，观察肾脏形态学变化及E-cadherin蛋白表达。结果CA组大鼠尿LDH活性和尿蛋白含量与对照组比较均明显升高。肾皮质GSH含量显著升高，MDA含量变化不明显。Cd组大鼠近端小管上皮细胞排列散乱，刷状缘大面积脱落。有局灶性的空泡变性。与对照组比较，Cd组中E-cadherin在肾小管上皮细胞的基底侧表达明显减少。结论在肾脏处于较低水平的氧化损伤时镉就可干扰体内肾小管上皮细胞E-cadherin依赖的黏附连接。E-cadherin是镉肾毒性的相对较早的靶部位；E-cadherin依赖黏附连接的损伤可能是镉肾毒性的一个重要机制。     

Fertility of the Monorchid Rat After Partial Resection of Testes

Regeneration of the seminiferous tubules was tested in mornorchid rats whose testes were resected 25%, 50%, and 75% of the wet weight of testis. After a 50-day recovery the animals were paired with primiparous rats to verify the male fertility. All the rats with 25% of testicular resection sired young, while those with 75% of resection were sterile. Among rats that suffered 50% of resection, only 17% were fertile. A comparative histomorphometry of the control testes and the resected testes demonstrated that parenchyma of the adult rat testis was not able to regenerate. However, the fertilizing capacity of rats depended on the amount of preserved testicular parencyma.     

Developmental Changes in Testosterone Production by the Rat Testis in Vitro During Late Fetal Life

The age-related evolution of the in vitro capacity of the rat testis to produce testosterone and to respond to luteinizing hormone (LH) during 3 and 24 h incubation was studied from day 18.5 to day 21.5 of fetal life. Basal testosterone production by testes from 18.5-day-old fetuses was significantly higher than production by testes from 20.5- and 21.5-day-old fetuses when secretion was expressed as either per testis or per microgram of testicular protein. When maximal LH-stimulated testosterone secretion was expressed on a per testis basis, it was significantly lower for day 18.5 testes than for day 20.5 and 21.5 testes. However, when it was expressed on the basis of testicular protein content, it decreased significantly between days 18.5 and 20.5. Basal and LH-stimulated secretions displayed the same time-related decrease throughout 24 h of incubation for the three ages studied. The dose-response curves for LH showed that the sensitivity was similar for day 18.5 and 20.5 testes (ED₅₀ = 10 vs. 14 ng/mL, respectively). These results showed an age-related decrease in testicular steroidogenic capacity without a change in the coupling efficiency of LH receptor to testosterone production during late fetal life in rats.     

EFFICACY OF INTRAUTERINE INSEMINATION WITHOUT OVARIAN HYPERSTIMULATION FOR MALE OR CERVICAL FACTOR IN WOMEN AGED 40 OR OVER

The aim of this study was to examine effects of photoperiod on the ultrastructure of Leydig cells in rat. For this purpose, 21 male Wistar rats were used. Animals were divided into three groups: Control rats in group I were kept under 12?hrs light: 12?hrs dark conditions (12L: 12D) for 10 weeks. Animals in group II were exposed to long photoperiods (18L: 6D), while rats in group III were exposed to short photoperiods (6L:18D) for 10 weeks. At the end of the experiment, all animals were killed by decapitation and blood samples were obtained. Serum testosterone levels were determined with the use of a chemiluminescent enzyme immunoassay. The testes of all rats were removed and weighed, then processed for light and electron microscopy. For morphometric comparison, diameters of seminiferous tubules in each group were measured. In rats exposed to long photoperiods, testicular weights, diameters of seminiferous tubules and serum testosterone levels were significantly increased as compared to those in control rats, whereas exposure of rats to short photoperiods resulted in a significant decrease of testicular weights, diameters of seminiferous tubules and serum testosterone levels as compared to those in control rats and rats maintained in long photoperiods. The amount of mitochondria and cytoplasmic secretory granules were increased in the cytoplasm of Leydig cells of rats exposed to long photoperiods. Furthermore, an increase in extensiveness of rough endoplasmic reticulum in the cell cytoplasm was noticed in this group, whereas a decrease in mitochondria and cytoplasmic secretory granules of the Leydig cell cytoplasm was seen in rats exposed to short photoperiods. The results of our study indicate that testicular functions increase after exposure to long photoperiods and decrease after exposure to short photoperiods.     

Protective Effects of Melatonin Against Formaldehyde-Induced Oxidative Damage and Apoptosis in Rat Testes: An Immunohistochemical and Biochemical Study

This study investigated the protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes. A total of 21 male Wistar rats were divided into three groups. Group I was used as a control, Group II was injected every other day with formaldehyde for 1 month, whereas Group III was injected every other day with formaldehyde and melatonin for 1 month. At the end of the experimental period animals were sacrificed and the testes removed and dissected from the surrounding tissues for immunohistochemical evaluation. In addition, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were determined. The levels of SOD and GSH-Px decreased significantly, whereas the level of MDA significantly increased in animals treated with formaldehyde compared with the controls. Apoptosis of spermatogenetic and Leydig cells of testicular tissues was observed. In contrast, rats with melatonin SOD and GSH-Px enzyme activity increased whereas MDA levels decreased with formaldehyde exposure along with apoptosis. In view of the present findings, it is suggested that melatonin treatment may prevent formaldehyde-induced oxidative damage and apoptosis in rat testes.     

Protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes: an immunohistochemical and biochemical study

This study investigated the protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes. A total of 21 male Wistar rats were divided into three groups. Group I was used as a control, Group II was injected every other day with formaldehyde for 1 month, whereas Group III was injected every other day with formaldehyde and melatonin for 1 month. At the end of the experimental period animals were sacrificed and the testes removed and dissected from the surrounding tissues for immunohistochemical evaluation. In addition, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were determined. The levels of SOD and GSH-Px decreased significantly, whereas the level of MDA significantly increased in animals treated with formaldehyde compared with the controls. Apoptosis of spermatogenetic and Leydig cells of testicular tissues was observed. In contrast, rats with melatonin SOD and GSH-Px enzyme activity increased whereas MDA levels decreased with formaldehyde exposure along with apoptosis. In view of the present findings, it is suggested that melatonin treatment may prevent formaldehyde-induced oxidative damage and apoptosis in rat testes.     

Effects of Cinnamon (C. zeylanicum) Bark Oil Against Taxanes-Induced Damages in Sperm Quality,Testicular and Epididymal Oxidant/Antioxidant Balance,Testicular Apoptosis,and Sperm DNA Integrity

The aim of this study was to investigate whether cinnamon bark oil (CBO) has protective effect on taxanes-induced adverse changes in sperm quality, testicular and epididymal oxidant/antioxidant balance, testicular apoptosis, and sperm DNA integrity. For this purpose, 88 adult male rats were equally divided into 8 groups: control, CBO, docetaxel (DTX), paclitaxel (PTX), DTX+PTX, DTX+CBO, PTX+CBO, and DTX+PTX+CBO. CBO was given by gavage daily for 10 weeks at the dose of 100 mg/kg. DTX and PTX were administered by intraperitoneal injection at the doses of 5 and 4 mg/kg/week, respectively, for 10 weeks. DTX+PTX and DTX+PTX+CBO groups were treated with DTX during first 5 weeks and PTX during next 5 weeks. DTX, PTX, and their mixed administrations caused significant decreases in absolute and relative weights of all reproductive organs, testosterone level, sperm motility, concentration, glutathione level, and catalase activity in testicular and epididymal tissues. They also significantly increased abnormal sperm rate, testicular and epididymal malondialdehyde level, apoptotic germ cell number, and sperm DNA fragmentation and significantly damaged the histological structure of testes. CBO consumption by DTX-, PTX-, and DTX+PTX-treated rats provided significant ameliorations in decreased relative weights of reproductive organs, decreased testosterone, decreased sperm quality, imbalanced oxidant/antioxidant system, increased apoptotic germ cell number, rate of sperm with fragmented DNA, and severity of testicular histopathological lesions induced by taxanes. In conclusion, taxanes cause impairments in sperm quality, testicular and epididymal oxidant/antioxidant balance, testicular histopathological structure, and sperm DNA integrity, and long-term CBO consumption protects male reproductive system of rats.     

Effects on rat testis of 1.95-GHz W-CDMA for IMT-2000 cellular phones

In recent years concern has arisen whether carrying a cellular phone near the reproductive organs such as the testes may cause dysfunction and particularly decrease in sperm development and production, and thus fertility in men. The present study was performed to investigate the effects of a 1.95 GHz electromagnetic field on testicular function in male Sprague-Dawley rats. Five week old animals were divided into 3 groups of 24 each and a 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is used for the freedom of mobile multimedia access (FOMA), was employed for whole body exposure for 5 hours per day, 7 days a week for 5 weeks (the period from the age of 5 to 10 weeks, corresponding to reproductive maturation in the rat). Whole-body average specific absorption rates (SAR) for individuals were designed to be 0.4 and 0.08 W/kg respectively. The control group received sham exposure. There were no differences in body weight gain or weights of the testis, epididymis, seminal vesicles, and prostate among the groups. The number of sperm in the testis and epididymis were not decreased in the electromagnetic field (EMF) exposed groups, and, in fact, the testicular sperm count was significantly increased with the 0.4 SAR. Abnormalities of sperm motility or morphology and the histological appearance of seminiferous tubules, including the stage of the spermatogenic cycle, were not observed. Thus, under the present exposure conditions, no testicular toxicity was evident.     

Effects on rat testis of 1.95-GHz W-CDMA for IMT-2000 cellular phones

In recent years concern has arisen whether carrying a cellular phone near the reproductive organs such as the testes may cause dysfunction and particularly decrease in sperm development and production, and thus fertility in men. The present study was performed to investigate the effects of a 1.95?GHz electromagnetic field on testicular function in male Sprague-Dawley rats. Five week old animals were divided into 3 groups of 24 each and a 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is used for the freedom of mobile multimedia access (FOMA), was employed for whole body exposure for 5 hours per day, 7 days a week for 5 weeks (the period from the age of 5 to 10 weeks, corresponding to reproductive maturation in the rat). Whole-body average specific absorption rates (SAR) for individuals were designed to be 0.4 and 0.08 W/kg respectively. The control group received sham exposure. There were no differences in body weight gain or weights of the testis, epididymis, seminal vesicles, and prostate among the groups. The number of sperm in the testis and epididymis were not decreased in the electromagnetic field (EMF) exposed groups, and, in fact, the testicular sperm count was significantly increased with the 0.4 SAR. Abnormalities of sperm motility or morphology and the histological appearance of seminiferous tubules, including the stage of the spermatogenic cycle, were not observed. Thus, under the present exposure conditions, no testicular toxicity was evident.     

稀土氟化钕对雄性大鼠睾丸毒性的影响

目的探讨稀土氟化钕(Nd F3)对雄性大鼠睾丸的影响。方法将48只SPF级健康成年雄性SD大鼠随机分为对照组和低、中、高剂量Nd F3染毒组,每组12只,采用非暴露式气管注入法建立大鼠损伤模型。3个染毒组分别灌注不同剂量的Nd F3溶液,染毒剂量分别为70、210、280 mg/kg,对照组予以相应体积的生理盐水,初次染毒间隔15 d后再次染毒,于第42天称重后处死。检测大鼠血清睾酮含量及附睾精子数量、精子存活率、精子畸形率。采用电感耦合等离子体质谱法测定大鼠睾丸组织Nd F3水平,在普通光镜下观察大鼠组织病理学改变,采用TUNEL法进行睾丸细胞凋亡检测,用透射电子显微镜进行睾丸组织超微结构检测。结果与对照组比较,各染毒组大鼠睾丸内Nd F3含量均增加,差异有统计学意义(P0.05);与对照组相比,低、高剂量组大鼠血清睾酮含量升高,中剂量组睾酮含量下降,且高剂量组睾酮含量低于低剂量组、高于中剂量组,差异均有统计学意义(P0.05)。与对照组相比,中、高剂量组大鼠精子数量、精子存活率降低,精子畸形率、睾丸细胞凋亡指数升高,差异有统计学意义(P0.05)。结论低剂量Nd F3颗粒物可促进大鼠睾丸发育,但中剂量Nd F3可损伤睾丸组织,进而可能影响雄性大鼠生殖功能。     

Nutraceuticals: A New Challenge against Cadmium-Induced Testicular Injury

Cadmium (Cd) is a widespread heavy metal and a ubiquitous environmental toxicant. For the general population, the principal causes of Cd exposure are cigarette smoking, air pollution and contaminated water and food consumption, whereas occupational exposure usually involves humans working in mines or manufacturing batteries and pigments that utilize Cd. The aim of the present review is to evaluate recent data regarding the mechanisms of Cd-induced testicular structural and functional damages and the state of the art of the therapeutic approaches. Additionally, as the current literature demonstrates convincing associations between diet, food components and men’s sexual health, a coherent nutraceutical supplementation may be a new valid therapeutic strategy for both the prevention and alleviation of Cd-induced testicular injury. The toxic effects on testes induced by Cd include many specific mechanisms, such as oxidative stress, inflammation and apoptosis. As no specific therapy for the prevention or treatment of the morbidity and mortality associated with Cd exposure is available, the development of new therapeutic agents is requested. Dietary strategies and the use of nutraceuticals, particularly abundant in fresh fruits, beans, vegetables and grains, typical of the Mediterranean diet, are recommended against Cd-induced testicular injury.     

Changes in male reproductive system and mineral metabolism induced by soy isoflavones administered to rats from prenatal life until sexual maturity

Objective

This study aimed to determine the influence of high-dose soy isoflavones (daidzein and genistein) administered from prenatal life to sexual maturity on testosterone and estradiol levels, testicular and epididymal morphology, the number of epididymal spermatozoa, and mineral metabolism in rats.

Methods

Pregnant Wistar rats received orally soy isoflavones, daidzein, and genistein at a dose of 200 mg/kg of body weight per day. After separating sucklings from their mothers, male rats received the same dose of isoflavones until reaching the age of sexual maturity, i.e., for 3 mo.

Results

In the isoflavone-treated group, statistically significant decreased concentrations of zinc (determined using atomic absorption spectrophotometry) in blood serum and increased concentrations in bone were observed. The isoflavones induced changes in the morphology of the seminiferous epithelium of rat testes. However, there were no significant changes in the number of spermatozoa in the epididymis. The levels of estradiol in serum and cauda epididymis homogenates of rats receiving phytoestrogens were significantly higher than in the control group. No differences were observed in testosterone concentrations in the serum of treated and control rats. The testosterone levels in the homogenates of the treated rat testes were significantly lower than in the control group.

Conclusion

The relatively mild effects of phytoestrogen administration on the morphology of testes and epididymides and the number of epididymal spermatozoa were observed despite the high dose used. The exposure of rats to genistein and daidzein during intrauterine life until sexual maturity influenced the mineral metabolism of the organism by significant decreases of Zn concentration in serum and increased Zn concentration in bones.     

邻苯二甲酸二(2-乙基己基)酯、氯氰菊酯单独及联合染毒对青春前期雄性大鼠生殖发育的不良影响

目的探讨邻苯二甲酸二(2-乙基己基)酯(DEHP)和氯氰菊酯(CYP)单独及联合染毒对青春前期雄性大鼠生殖发育的不良影响。方法选择SPF级3周龄雄性SD大鼠24只,随机分为4组,分别为对照组(喂饲玉米油)、DEHP染毒组(500mg/kg)、CYP染毒组(80mg/kg);DEHP、CYP联合染毒组(DEHP 500mg/kg+CYP 80mg/kg),每组6只。采用经口灌胃方式染毒,每天1次,连续染毒30天。于末次染毒24小时后处死动物,测定大鼠体重、睾丸湿重,并计算睾丸系数;测定血清睾酮水平;制备睾丸病理组织切片,光镜观察其组织学改变,电镜观察生殖细胞超微结构;测定睾丸标志酶乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)、碱性磷酸酶(ALP)和琥珀酸脱氢酶(SDH)的活性。结果与对照组相比,DEHP、CYP单独及联合染毒组睾丸下降时间和包皮分离时间明显延迟,肛门生殖器间距明显缩短(P<0.05或0.01);DEHP单独染毒组睾丸重量及睾丸系数明显降低,血清睾酮水平显著下降(P<0.05),睾丸匀浆中ALP、ACP和LDH活性明显增高,SDH活性显著下降(P<0.01);DEHP、CYP单独及联合染毒组睾丸病理组织学、生殖细胞超微结构均可见明显异常。结论 DEHP、CYP单独及联合染毒对青春前期雄性大鼠均具有明显的生殖毒性作用,可引起生精细胞、支持细胞和间质细胞的变性、坏死及功能障碍,从而导致雄性生殖系统发育和功能的显著异常。其中,DEHP单独染毒呈现主效应,DEHP、CYP联合染毒对大鼠的生殖毒性未呈现明显交互影响。