Hormonal control of the anatomical specificity of motoneuron-to-muscle innervation in rats

Motoneurons of the spinal nucleus of the bulbocavernosus innervate bulbocavernosus muscles in male rats. Adult female rats normally lack both the spinal nucleus and its target muscles. Prenatal treatment of females with testosterone propionate resulted in adults having, like males, both the spinal nucleus and its target muscles. However, prenatal treatment with dihydrotestosterone propionate preserves the muscles but not the motoneurons. This paradoxical condition might result from (i) bulbocavernosus muscles without innervation; (ii) muscles innervated by morphologically unrecognizable motoneurons; (iii) muscles innervated by a very few spinal nucleus cells, each innervating many bulbocavernosus fibers; or (iv) muscles innervated by motoneurons outside their normal anatomical locus in the spinal nucleus. The results of retrograde marker injections into the bulbocavernosus muscles of females treated with androgen refute the first three possibilities and confirm the last: the different androgen treatments result in anatomically distinct spinal motor nuclei innervating bulbocavernosus muscles.     

Pineal gland: influence on gonads of male rats treated with androgen 3 days after birth

Either blinding or the injection of 1 milligram of testosterone propionate into male Sprague-Dawley rats, 3 days old, results in testes and accessory organs (seminal vesicles and coagulating glands) that are smaller than normal when the rats are 72 days old. The response to blinding is prevented by removal of the pineal gland, whereas the response to treatment with testosterone is unaffected by pinealectomy. Combination of the two treatments in 3-day- old rats causes testes to be less than one-third their normal size at 72 days of age; pinealectomy in these rats permits the reproductive organs to grow to the same size as those in the androgen-treated animals.     

丙酸睾酮对鸡胚性腺发育和成活率的影响

研究丙酸睾酮的剂量与注射时间对早期鸡胚性腺发育和成活率的影响。选择320枚种蛋(蛋重60.00 g±0.10 g),在入孵的0、3、6、9 d分别向蛋清内注射0.00、0.05、0.10和0.20 mL丙酸睾酮,共16个处理水平,孵化18 d后,形态学观察鸡胚性腺发育,统计其成活率及胚重。结果表明,丙酸睾酮对鸡胚性腺发育有显著影响(P<0.05),公鸡左侧睾丸或母鸡右侧卵巢发育均受到不同程度的影响。鸡胚性腺异常占总数的19.88%,其中公鸡占性腺异常总数的6.02%,母鸡占性腺异常总数的13.86%,且存在0.60%间性。随处理剂量的上升,鸡胚成活率及平均胚重不断下降,且随处理时间的延长,鸡胚成活率及胚重受到的影响程度逐渐降低。     

集约经营措施对毛竹林生长季土壤呼吸的影响

以粗放经营毛竹Phyllostachys pubescens林和常绿阔叶林作为对照,利用静态箱-气相色谱法研究集约经营对毛竹林土壤呼吸速率的影响。结果显示：整个生长季（4-10月）,集约经营毛竹林、粗放经营毛竹林和常绿阔叶林之间土壤平均呼吸速率存在差异显著（P〈0.05）,3种林分土壤平均呼吸速率分别为1.01,0.79和0.72 g.m-2.h-1。3种林分土壤呼吸速率动态变化规律基本一致,4-5月土壤呼吸速率相对较小,6月开始迅速升高,7月达到最大值,6-9月维持在较高值,10月开始大幅度下降。土壤呼吸与地下5 cm土壤温度呈显著的指数相关（P〈0.05）,3种林分地下5 cm深处土壤温度分别可以解释土壤呼吸变化的63%,63%和59%。根据集约经营毛竹林、粗放经营毛竹林和常绿阔叶林土壤呼吸与地下5 cm土壤温度拟合的指数方程,计算出生长季土壤呼吸的温度系数Q10值分别为2.46,4.81和2.05。图2表1参40     

Mice: fighting by neonatally androgenized females

Administration of testosterone propionate to female mice on the day of birth resulted in increased fighting after administration of testosterone during adulthood. This fighting, comparable to fighting among normal male mice, suggests that early androgenic stimulation organizes neural structures mediating aggression in the mouse.     

Aggression in adult mice: modification by neonatal injections of gonadal hormones

Incidence of spontaneous aggression in adult male mice given a single injection of estradiol benzoate (0.4 milligram) when they were 3 days old was less than that of controls injected with oil. Aggressiveness was increased among adult females injected with either estradiol or testosterone propionate (1 milligram) at the same age. The increased aggressiveness noted among females given androgen was further documented during subsequent mating tests, when these females often attacked, wounded, and, in one case, killed naive males.     

Sexual behavior: normal male patterning in androgenized female rats

Female rats treated with testosterone as neonates and as adults exhibited a temporal patterning of male copulatory behavior identical to that of normal males, although such females displayed few intromission reflexes and almost no ejaculatory patterns. With prenatal, postnatal, and adult testosterone treatment, female rats displayed all the characteristic masculine responses and intervals, including the ultrasonic postejaculatory vocalization.     

Influence of Anabolic Steroids on Uptake of Alpha-Aminoisobutyric Acid by Levator Ani Muscle

Two representative anabolicsteroids caused an increase in the uptake of alpha-aminoisobutyric acid-1-C(14) in the levator ani muscle of rats. The distribution ratio between that muscle and the plasma was increased fourfold by the administration of a synthetic anabolic steroid and twofold by administration of testosterone propionate. The determination of this increase may serve as an indicator for the myotrophic effect of anabolic steroids.     

外源雄激素促进绵羊附睾GPx5基因的表达

为研究外源雄激素丙酸睾酮对绵羊附睾特异表达基因谷胱甘肽过氧化酶5(GPx5)的影响,应用酶联免疫吸附(ELISA)法检测血清和附睾头部内睾酮(T)、二氢睾酮(DHT)的含量,及附睾头部雄激素受体(AR)蛋白表达量;应用实时荧光定量PCR(RT-PCR)技术检测了附睾头部GPx5-mRNA和AR-mRNA相对表达量;并结合免疫印迹(WB)法检测了附睾头部GPx5蛋白相对表达量。结果表明:丙酸睾酮处理(TPT)组与对照组相比绵羊血清DHT含量,附睾头部T含量、DHT含量均显著提高,分别是对照组的0.5、6.0、0.8倍;GPx5-mRNA和ARmRNA相对表达量显著提高,分别是对照组的0.75和0.77倍(P0.05);AR及GPx5蛋白表达量显著提高,分别是对照组的0.63和0.58(P0.05)。因此,外源雄激素丙酸睾酮可大量提高绵羊附睾头部GPx5基因的表达,对绵羊附睾头部GPx5基因的表达具有促进作用。     

HPLC-MS法测定猪肉中地西泮等5种禁用药物的残留量

[目的]建立快速、准确、高灵敏度的测定猪肉中地西泮等5种禁用药物残留量的分析方法。[方法]采用高效液相色谱-串联质谱联用法(HPLC-MS),通过不同的离子模式进行猪肉中5种禁用药物残留量的测定,其中地西泮、丙酸睾酮、氯丙嗪采用正离子模式,玉米赤霉醇以及己烯雌酚采用负离子模式,并进行多反应检测(MRM)。[结果]试验显示,该方法的线性范围为:3~100 ng/m L,标准曲线线性良好,其回归方程及相关系数分别为地西泮:Y=27 200X-0.009 31,R=1.000 0;丙酸睾酮:Y=13 800X-0.000 147,R=1.000 0;氯丙嗪:Y=0.095 1X+0.025 7,R=0.999 9;玉米赤霉醇:Y=44 100X-0.006 58,R=1.000 0;己烯雌酚:Y=0.093 4X+0.018 8,R=0.998 9。回收率分别为:地西泮100.50%~111.30%;丙酸睾酮73.30%~84.20%;氯丙嗪70.30%~99.10%;玉米赤霉醇69.90%~75.30%;己烯雌酚84.70%~117.70%。最低检出限分别为:地西泮0.4μg/kg,丙酸睾酮0.6μg/kg,氯丙嗪0.3μg/kg,玉米赤霉醇0.5μg/kg,己烯雌酚0.8μg/kg。[结论]该方法操作简便、快速,是动物源性食品中地西泮等5种禁用药物残留的快速而准确的检测方法。     

钼暴露对不同性别SD大鼠血气相关指标的影响

为了研究钼对SD大鼠血气相关指标的影响,试验选用健康状况良好的SD大鼠60只(雌雄各30只),雌雄鼠分别随机分为5组,即对照组、钼50组、钼100组、钼200组、钼400组,适应后进行试验,自由进食及饮水,分别在饮水中添加0、50、100、200、400mg·L-1钼酸钠(Na2MoO4·2H2O),以此建立试验动物模...     

雄激素对去势大鼠弓状核AR蛋白表达的影响

为了探讨雄激素（androgen）对去势大鼠弓状核（ARC）内雄激素受体（AR）表达的影响。将30只3月龄雄性健康SD大鼠随机分为GM组（睾丸摘除组）、IMC组（假手术组）、GM＋T组（睾丸摘除并用睾酮替代组）,注射雄激素4周后灌注取材。结果表明,睾九摘除组大鼠弓状核内AR蛋白的表达显著减少,睾丸摘除并用睾酮替代组大鼠弓状核内AR蛋白的表达接近正常水平。说明去睾丸大鼠由于缺乏内源性雄激素,引起弓状核内AR蛋白表达减少,而补充外源性雄激素可抑制这一变化。     

Antireproductive effects of a potent gonadotropin-releasing hormone antagonist in the male rat

Administration of a potent antagonist of gondadotropin-releasing hormone (GnRH) antagonist [Ac-dehydro-Pro1, pCl-D-Phe2, D-Trp3,6]-N alpha-MeLeu7-GnRH to adult male rats for 2 weeks resulted in decreased testosterone production and sexual organ weights and in disrupted spermatogenesis. The results demonstrate the essential role of gonadotropin-releasing hormone in the maintenance of reproductive functions and have implications for the regulation of male fertility.     

育雏期母鸡母性行为消长试验初报

本试验采用母子共处或隔离以及注射丙酸睾丸酮的方法,对育雏期母鸡母性行为的消长进行了初步观察。试验结果初步说明,催乳激素是维持母鸡母性行为的物质基础,雏鸡形态、叫声、母子间的体表接触则是维持母鸡催乳激素含量在所需水平的首要条件。     

Neonatal castration: influence on neural organization of sexual reflexes in male rats

Most male rats castrated 4 days after birth and given exogenous testosterone in adulthood were sexually motivated but incapable of completing the mating sequence with an ejaculatory response. When tested for sexual reflexes after spinal transection, these animals displayed impairment of genital responses. Similarly treated 12-day castrates exhibited a complete mating sequence and had normal sexual reflexes. Thus neonatal testicular androgen appears to have an organizational influence at the spinal level on neural tissue mediating sexual reflexes.     

Testosterone regulation of sexual reflexes in spinal male rats

Castrated male rats with complete midthoracic spinal transections were maintained on exogenous testosterone; they showed intermittent clusters of genital responses consisting of erections, quick flips, and long flips of the penis when gentle pressure was con stantly applied to its base. The number of these genital responses per 30-minute test was markedly influenced by withdrawal or administration of testosterone.     

延胡索酸对瘤胃微生物发酵活力及乳酸浓度的影响

分别以0.6 g玉米粉+0.4 g稻草片段(3 mm)及1 g稻草片段(3 mm)为底物,收集装有永久性瘤胃瘘管的4头本地山羊的瘤胃液,在体外厌氧条件下,研究了不同浓度(4、8、12 mmol.L-1)延胡索酸对瘤胃微生物发酵活力的影响.结果表明,与对照组相比,各浓度延胡索酸均可显著提高体外培养体系中总产气量和总挥发性脂肪酸浓度,提高总挥发性脂肪酸中丙酸的含量,降低乙酸与丙酸的浓度比和发酵液中乳酸的浓度(P<0.05),显著提高瘤胃微生物对稻草的降解率(P<0.05),且对各指标的影响程度具有明显的剂量效应.因此,延胡索酸可提高瘤胃微生物体外发酵活力,减少乳酸累积量.     

Liver cancer: neonatal estrogen enhances induction by a carcinogen

A single injection of 100 micrograms of estradiol benzoate into newborn rats was followed after weaning by dietary treatment with one of two dosages of the carcinogen N-hydroxy-N-2-fluorenylacetamide. Autopsies 26 weeks later showed a higher incidence of liver cancer in male and, particularly, female rats injected with hormone than in controls. The weights of livers were greater but gonads were smaller in size in the estradiol groups. Endocrine and possibly centralnervous-system factors may play roles in formation of liver tumors.     

制霉菌素抗饲料霉变性能的研究

以蛋鸭料为基础，分别在粉状料和颗粒料中添加制霉菌素、丙酸钙、霉敌３种抗真菌制剂，比较了三种抗真菌剂的抗饲料霉变功效．结果表明：颗粒料中的真菌比粉状料明显降低，３种抗菌制剂都有明显的抗真菌效果．其中制霉菌素与霉敌的抗霉菌生长效果优于丙酸钙，并能完全抑制黄曲霉、毛霉、根霉的生长，制霉菌素能显著降低饲料中黄曲霉毒素Ｂ１的含量．添加制霉菌素后粉状料的保质期为５０ｄ，颗粒饲料为６０ｄ，与霉敌基本一致：粉状料添加制霉菌素组比丙酸钙组保质期延长１０ｄ，颗粒料保质期可延长２０ｄ左右．几种处理条件下，当日粮中真菌总数发生明显变化时，饲料中ＣＯ２量也明显增加，因此，应用饲料中ＣＯ２含量作为衡量霉菌总数是一个比较敏感的指标．     

大豆黄酮对反刍动物血清睾酮和瘤胃消化代谢的影响

大豆黄酮对雄性湖羊及水牛血清睾酮和瘤胃消化代谢影响的研究发现：雄性湖羊连续 ７ ｄ 皮下注射大豆黄酮（ １００ ｍ ｇ／ｋｇ 体重）,血清睾酮水平明显增加; 雄性水牛经十二指肠瘘管灌注大豆黄酮（５００ ｍ ｇ／ｄ）,连续 １２ ｄ,血清睾酮（ Ｐ＜ ０．０５）、瘤胃细菌蛋白（ Ｐ＜ ０．０１）、挥发性脂肪酸（ Ｐ＜ ０．０５）和 Ｈ Ｎ３  Ｎ （ Ｐ＜ ０．０１）显著增加,但（ Ｃ２ ＋ Ｃ４ ）／ Ｃ３ 未见有明显变化。结果表明： 大豆黄酮可以提高血清睾酮水平,并改善瘤胃微生物消化代谢。