孕期二月桂酸二丁基锡暴露对子代大鼠睾丸酶活力和生精功能的影响

目的 探讨孕期接触二月桂酸二丁基锡(DBTD)对Wistar大鼠子代雄性鼠性成熟后睾丸酶活力和生精功能的影响.方法 以0、10、20和30 mg/kg剂量的DBTD溶液对妊娠第12天的Wistar孕鼠连续灌胃染毒至第20天,仔鼠出生后第70天,每组随机抽取10只雄性大鼠,称重并处死,测定睾丸脏器系数、附睾精子数,并采用分光光度法测定睾丸酶活力.结果 各剂量组孕鼠染毒期间体重增加量、产仔数、仔鼠雌雄比例及子代雄性大鼠体重与对照组比较,差异均无统计学意义(P＞0.05);30 mg/kg组睾丸重量和睾丸脏器系数高于对照组,差异有统计学意义(P＜0.01,P＜0.05);20和30 mg/kg组精子数高于对照组,差异有统计学意义(P＜0.05,P＜0.01).各剂量组琥珀酸脱氢酶(SDH)活力和一氧化氮合酶(NOS)活力与对照组比较,差异无统计学意义(P＞0.05);10和20 mg/kg组酸性磷酸酶(ACP)活力、10 mg/kg组乳酸脱氢酶(LDH)活力、30 mg/kg组一氧化氮(N0)含量均高于对照组,差异有统计学意义(P＜0.05).结论 在本实验染毒时间和剂量范围内,DBTD对子代雄性大鼠睾丸发育和精子形成有促进作用,而对睾丸酶活力无直接影响.     

雄性生殖系统中瘦素表达及功能的研究进展

男性生育力呈下降趋势,阐明其发生机制有助于男性不育症的精准医疗.瘦素是一种主要由脂肪组织产生的激素,在调节机体能量代谢、参与炎性反应、促进生殖系统发育及维持其正常功能等方面具有重要的作用.瘦素及其受体在哺乳动物下丘脑-垂体-性腺(HPG)轴的内分泌器官、睾丸、生殖道、附属生殖腺以及精子中均有广泛表达,其表达异常与雄性生...     

青春期SD大鼠单侧睾丸扭转后FAS/FASL系统变化的研究

目的初步研究青春期一侧睾丸扭转SD大鼠性成熟后对侧睾丸的FAS/FASL系统的表达与对侧睾丸生精功能的变化情况的相互关系.方法建立青春期SD大鼠一侧睾丸扭转模型5组,A组为假手术对照组;B组为睾丸扭转组;C组为睾丸扭转+甲强龙组;D组为扭转侧睾丸切除组;E组为扭转侧睾丸切除+甲强龙组.于扭转后24h给予睾丸切除或/和注射甲强龙处理,术后1月处死,取对侧睾丸组织,HE染色检查,用免疫组织化学染色法检测睾丸生精细胞,支持细胞的FAS及FASL的表达情况,并对FAS及FASL的表达作定量分析.用放射免疫法检测血清中FSH,LH,T的值并做分析.结果 B组对侧非扭转睾丸的形态有病理性改变.各组睾丸组织同时表达FAS和FASL,B组的FAS和FASL的表达强度较其他各组有明显的升高.各组血清中FSH,LH,T的值没有统计学差别.结论青春期SD大鼠单侧睾丸扭转后对侧睾丸生精细胞发生FAS和FASL的高表达,从而导致细胞的凋亡增加,生育力下降.皮质激素可能通过抑制FAS和FASL的表达,降低生精细胞的凋亡,维持生精功能的稳定.     

精原细胞移植的发展与现状

精原细胞移植 (ST)的原理与其他器官移植类似 ,主要通过显微外科技术 ,将供体精原细胞注入受体 ,利用受体微环境使供体细胞分裂分化为精子。根据供体类型以及实验目的 ,将ST分类。其中 ,同种间细胞移植已经获得成功 ,而异种移植 (以人、马、牛、大鼠等为供体 ,免疫缺陷小鼠为受体 )、冰冻细胞移植均未成功 ,其原因可能与免疫排斥反应有关。ST有利于 :①精子发生过程的研究 ,②男性不育症的研究 ,③转基因动物的研究     

筛选人睾丸特异性含溴结构域蛋白(BRDT)的小分子抑制剂

目的睾丸特异性含溴结构域的蛋白(BRDT)在睾丸中特异表达,参与精子生成的染色质重组过程。本文虚拟筛选基于结构的人BRDT小分子抑制剂。方法从PDB(Protein Data Bank)下载BRDT核心结构域与小分子抑制剂JQ1结合结构域的晶体结构(PDB ID:4FLP),利用分子模拟软件Discovery Studio 3.0,构建了其活性位点抑制剂的药效团模型。运用最佳药效团模型对10 000个化合物的数据库进行初筛,随后运用Libdock分子对接方式对初筛得到的潜在目标化合物进行复筛;最后运用BRDT Bromodomain TR-FRET Assay方法,对虚拟筛选得到的化合物进行实物筛选。结果运用虚拟筛选和蛋白水平筛选相结合的方法,从40 000个化合物中最终得到1个对BRDT有较高抑制作用的小分子抑制剂T480。结论利用一种基于结构的集合虚拟筛选与蛋白水平筛选的BRDT抑制剂的高通量筛选方法,筛选到BRDT的一个小分子抑制剂。     

Recent advances in hormonal male contraception

Hormones inhibit fertility in men by suppressing sperm production. Testosterone-enanthate induced azoospermia has proven to provide optimal contraceptive protection. Preliminary studies have shown that testosterone alone or androgen-progestin combinations induce profound sperm suppression in the Eastern and white populations, respectively. Thus, these regimens may represent viable options for male contraception. New long-acting androgen formulations represent a major advancement in this field, allowing for the development of more acceptable and effective regimens.     

大剂量PGE对大鼠生精作用及组织PG含量的影响

PGE每天3.0mg/kg皮下注射22天,除使大鼠付睾精于活率下降、畸形率升高外,也可损伤生精细胞,最敏感者为早期精子细胞和初级精母细胞,偶尔损及精原细胞。对间质和支持细胞无明显影响。给大剂量PGE后,大鼠血浆和肾皮质PGE水平无明显改变,而睾丸组织中则显著升高。     

Preclinical evaluation for noninvasive reversal following long-term vas occlusion with styrene maleic anhydride in langur monkeys

A preclinical evaluation for reversal through a noninvasive approach following long-term vas occlusion with styrene maleic anhydride (SMA) has been attempted in langur monkeys at the level of semen parameters, sperm functional tests, semen biochemistry, histology and ultrastructure of reproductive organs, hematology and serum clinical biochemistry including antisperm antibodies (ASA), prostate-specific antigen (PSA) and testosterone. Noninvasive reversal through palpation, percutaneous squeezing and electrical stimulation, forced vibratory movements and suprapubic percussion in the inguinal segments and per-rectal digital massage was attempted in seven langur monkeys after 540 days following vas occlusion. The results revealed instant azoospermia reversal on the same day of reversal with impaired sperm quality, which showed gradual improvement and normospermia with normal motility and viability after 60-90 days of reversal. Sperm functional tests, including ultrastructure of spermatozoa, indicative of sterility in the initial ejaculations, reached normalcy after 90-120 days of reversal. The seminal plasma biochemistry indicative of obstructive azoospermia regained a normal pattern after 90-120 days of reversal. The morphology of testes that showed focal degeneration during 540 days of vas occlusion and that of vasa deferentia that showed exfoliation of epithelial cells resumed to normal morphology comparable with control animals after 150 days of reversal. The morphology of the epididymis, seminal vesicle and prostate did not show appreciable changes following vas occlusion and after noninvasive reversal compared with those of control animals. Hematology, serum clinical chemistry, ASA, PSA and testosterone fluctuated within control limits, indicating safety of the procedure at the level of accessory reproductive organs. The results suggest that noninvasive reversal is feasible even after long-term vas occlusion with SMA and is safe without adverse side effects.     

Frequency of stages of the seminiferous cycle in the thick-tailed bush baby (Otolemur garnetti), a prosimian primate: possible phylogenetic implications?

Spermatogenesis in the thick-tailed bush baby, Otolemur garnetti, was studied using light microscopy. The stages and stage frequencies of the cycle of the seminiferous epithelium were determined using semithin sections stained with methylene blue-azure II. These sections were obtained from the testes of six healthy adult males (n=6). They revealed 11 stages of the seminiferous epithelial cycle in this species. The mean relative frequencies of the stages I–XI were 10.9, 6.0, 5.9, 7.3, 13.2, 10.7, 11.7, 9.2, 7.6, 8.9 and 8.6, respectively. Comparisons were made between the frequency data in the thick-tailed bush baby and equivalent data in the rat, hamster, macaque, baboon, chimpanzee and man. There was a significant correlation (P<0.05) between the Otolemur data and equivalent stage frequency data of two rodent species (rat and hamster) and monkey (Macaca arctoides). However, there was no significant correlation between the present data and those of the baboon, chimpanzee and man. Possible phylogenetic implications of these findings are discussed.