β-酪啡肽对公山羊血清FSH、LH和T水平的影响

给公山羊瘤胃灌注β－酪啡肽（β－CM）,在灌注前后采取外周血样,用放射免疫分析法测定血清促卵泡素（FSH）、促共体生成素（LH）和睾酮（T）水平,旨在研究β－酪啡肽对公山羊生殖内分泌的影响。结果表明,瘤胃灌注β－CM后,公山羊血清LH和T水平明显降低（P＜0．01或P＜0．05）,且此效应可被阿片受体拮抗内络酮（naloxon）逆转,而β－CM灌注,对公山羊血清FSH水平未昂明显影响（P＞0．05）。     

Suppression of ovulation in the rat by an orally active antagonist of luteinizing hormone-releasing hormone

A synthetic antagonist of luteinizing hormone-releasing hormone blocked ovulation in rats in a dose-dependent manner when given by gavage on the afternoon of proestrus. Ovulation was delayed for at least 1 day in all animals given 2 milligrams of antogonist and in some of the animals treated with 1 or 0.5 milligram. Oral administration of 2 milligrams also blocked the preovulatory surge of luteinizing hormone. This demonstration that antagonists of luteinizing hormone-releasing hormone can have oral antiovulatory activity clearly enhances their therapeutic potential.     

A parathyroid hormone inhibitor in vivo: design and biological evaluation of a hormone analog

A synthetic analog of bovine parathyroid hormone (bPTH), [tyrosine-34] bPTH-(7-34)NH2, was found to inhibit parathyroid hormone action in vivo. When the analog and parathyroid hormone were infused simultaneously to rats at a molar ratio of 200 to 1, the analog inhibited the excretion of urinary phosphate and adenosine 3',5'-monophosphate. When infused alone at the same dose rate, the analog was devoid of agonist activity. The compound was prepared by following design principles developed for inhibitors of parathyroid hormone, and is believed to be the first antagonist of parathyroid hormone that is effective in vivo.     

Stress-induced inhibition of reproductive functions: role of endogenous corticotropin-releasing factor

In the adult castrated male rat, exposure to inescapable, intermittent electroshocks inhibited the pulsatile pattern of luteinizing hormone release and markedly lowered its plasma concentrations. The central administration of the corticotropin-releasing factor (CRF) antagonist alpha-helical ovine CRF residues 9 to 41 reversed the inhibitory action of stress. Neither its peripheral injection, nor the intraventricular injection of the inactive CRF analog des-Glu to Arg ovine CRF was effective. These results suggest that endogenous CRF may mediate some deleterious effects of noxious stimuli on reproduction.     

甲壳动物生长发育的激素调控研究概述

蜕皮贯穿甲壳动物生长发育的始终。概述了调控甲壳动物蜕皮的主要内分泌腺(Y-器官、大颚器官、X-器官窦腺复合体等)以及外源性激素(高等动物性激素、脊椎动物生长激素、外源性蜕皮激素和外源性保幼激素拮抗物),其中保幼激素拮抗物作为甲壳动物促生长剂,高效、低成本、相对安全。     

Annual Change of the Testosterone Hormone in Male White Goats

In this research, changes of testosterone hormone in the blood serum of 9 male (3 of age 2 and 6 of age 4) White goats have been studied for a duration of one year. Analyses performed show that the general monthly averages of the testosterone hormone of the male White goats in the period of 12 months starting in January were (2.11±0.73), (2.22±0.52), (2.44±0.59),(2.10±0.41),(2.35±1.00), (3.42±1.48), (4.77±1.32), (5.61±1.40), (7.91±1.24), (10.84±1.59), (7.82±1.60), and (2.63±0.61) ng mL-1,respectively (P<0.05). The effect of the age factor on the testosterone production in White goats (age 2 and 4) was generally significant (P<0.05) for differences among months in each age group, but not significant for differences between age groups in each month. The testosterone hormone levels of male White goats encountered significant changes (P<0.05)with respect to the season.     

番茄温敏核不育系花药培养诱导愈伤组织的研究

[目的]探讨影响番茄温敏核不育系花药培养诱导愈伤组织的相关因子。[方法]研究不同灭菌处理、不同基本培养基、不同激素种类及浓度对番茄温敏核不育系花药培养诱导愈伤组织的影响。[结果]0．1％HgCl28min＋10％NaClO8min的灭菌处理效果最佳,菌污染率仅为1．95％,出愈率达71．73％;在MS、B5Miller3种基本培养基的比较试验中,以MS为基本培养基对花药愈伤组织的诱导效果最好;诱导愈伤组织的适宜浓度为2,4-D1mg／L、6-BA2mg／L、KT2mg／L。[结论]灭菌处理、基本培养基、激素种类及浓度可以影响番茄温敏核不育系花药培养诱导愈伤组织的效果。     

Enhancement of sexual motivation in male rats by yohimbine

Yohimbine hydrochloride, an alpha 2-adrenoceptor antagonist, increased sexual motivation in male rats as evidenced by increased mounting performance in mating tests conducted after genital anesthetization, increased percentage of male rats ejaculating in their first heterosexual encounter, and induction of copulatory behavior in sexually inactive male rats. These observations lead to the suggestion that alpha-adrenoceptors are important modulators of sexual arousal in intact male rats. These results indicate that pharmacological treatment of sexual (libido) dysfunction may be useful.     

Prolactin and growth hormone release by morphine in the rat: different receptor mechanisms

Concentrations of prolactin and growth hormone in the serum of rats were significantly increased by morphine. Dose response studies demonstrated that maximum prolactin release required lower doses of morphine than those needed for the maximum growth hormone response. Selective blockade of mu 1 (high affinity) opiate receptor with the irreversible antagonist naloxazone reduced morphine-induced peak concentrations of prolactin by 80 percent while increasing peak growth hormone levels by 250 percent. These results suggest different receptor mechanisms for the opiate modulation of the two hormones. The mu 1 (high affinity) receptor sites appear to mediate the morphine-induced release of prolactin but not growth hormone.     

甲基睾丸素对中华鳖外部性征诱导作用的研究

采用甲基睾丸素处理不同发育时期的中华鳖胚胎和给孵出后３ｄ的稚鳖拌饲甲基睾丸素来观察外源性激素的诱导作用,结果表明：试验组与对照组的孵化率无显著差异。说明孵化率不受生激素处理的影响,经雄性激素处理过的所有个体外部雄性副性征明显,其尾巴长,露出背板的裙边,且好咬斗,这充分证明外源雄性激素对稚鳖的外部性征及胃较大的诱导作用。     

Homologous regulation of gonadotropin-releasing hormone receptors in cultured pituitary cells

Specific receptors for gonadotropin-releasing hormone (GnRH) in cultured rat pituitary cells were increased by subnanomolar concentrations of GnRH agonists and decreased by high concentrations of these peptides. The antagonist [D-Phe2, Pro3, D-Phe6]GnRH did not alter GnRH binding capacity and blocked the increase in sites induced by GnRH. These findings provide direct evidence for the homologous regulation of GnRH receptors by physiological concentrations of the hypothalamic peptide, an action that could mediate the cyclical and postcastration increases in GnRH receptors and responsiveness of the pituitary gonadotrophs.     

A role for glycosylation of the alpha subunit in transduction of biological signal in glycoprotein hormones

The biological properties of recombinants of glycoprotein hormones in which the alpha and beta subunits were differentially deglycosylated have been investigated. Specific deglycosylation of the alpha subunit generated a recombinant that had more receptor-binding activity but did not produce hormone response in the target cells. The deglycosylated alpha + beta recombinant was also an antagonist of the action of the native hormone. Thus, the carbohydrates in the alpha subunit play a dominant role in the transduction of the hormone signal into the cell.     

Role of enzymatic wall-softening in plant morphogenesis: hormonal induction in Achlya

Sexual hormone A, which induces antheridial branching in male strains of Achlya, also elicits a rise in cellulase. The peak of induced cellulase corresponds in time with the appearance of branches that are the male sexual organ primordia; only those strains that branch in response to the hormone show a concomitant rise in cellulase. The response to the hormone is inhibited by compounds that block protein synthesis, for example, p-fluorophenylalanine and puronmycin. Vegetative branching, induced by substrates such as casein hydrolysate, is also accompanied by a rise in cellulase.     

Pheromone-induced changes in the acidophil concentration of mouse pituitary glands

Pituitaries of female mice in anestrus resulting from colony housing were characterized by a 58.0-percent (acidophil content. Subsequent exposure to restrained male mice for one and two nights failed to evoke significant acidophilic degranulation and resulted in pituitary acidophil values of 57.4 and 55.1 percent respectively. Exposure to released males on the third night produced marked acidophilic degranulation resulting in a significant decline in pituitary acidophils to 38.0 percent. These findings support the view that female pheromone suppresses and male pheromone favors the secretion of follicle-stimulating hormone and indicate that luteotrophic hormone is secreted at its assigned time in the sequence of cyclic ovarian events initiated by the secretion of follicle-stimulating hormone.     

Male contraception; synergism of gonadotropin-releasing hormone analog and testosterone in suppressing gonadotropin

Long-term administration of either superactive analog's of gonadotropin-releasing hormone or of testosterone suppresses gonadotropin secretion in male animals and humans. Testosterone administered in combination with gonadotropin-releasing hormone analog further suppresses serum gonadotropin levels in male rats. This observation indicates synergistic activity and suggests that the gonadotropin-releasing hormone analog and testosterone act at independent sites within the hypothalamic-pituitary axis. The primary actions of superactive analog are probably mediated by changes at a postreceptor site in the pituitary gonadotropin-secreting cells.     

花椰菜雄性不育材料的鉴定和繁殖

以花椰菜的雄性不育材料和可育材料为试材,通过对其花器组成进行鉴定,研究不育材料和可育材料之间的差异。结果表明:不育株和正常株的花朵的组成之间存在差异,不育株的花器明显比可育株小,雄蕊萎缩在基部,不产生花粉。同时,采用组织培养和扦插的方法对其不育材料的繁殖进行研究,发现在组织培养中,茎段和花球比叶片和叶柄容易繁殖,扦插中,ABT2号生根粉的扦插效果好于生长素IAA,同时,对不同扦插基质的研究发现,蛭石作为扦插的基质优于炉灰渣。     

紫菜薹细胞质雄性不育系及其保持系在不同发育时期内源激素的变化

利用酶联免疫测定技术研究了紫菜薹细胞质雄性不育系和保持系不同发育时期的生长素IAA、赤霉素GA和玉米素核苷ZR的动态变化.结果表明,内源IAA、GA、ZR含量在生殖器官和营养器官保持系和两种不育系都表现出显著性变化,改良萝卜不育系和ogura不育系的内源激素含量在植物发育的各个时期也存在差异.苗期ZR含量主要集中于根部,保持系根部ZR含量最高;幼根保持系IAA含量显著高于不育系,幼苗期叶片IAA含量相差不大;不育系与保持系苗期不同器官GA含量分布不均衡.在花期叶片激素含量在保持系和不育系之间变化较大,蕾期不育系的IAA、GA和ZR含量出现不同程度的亏缺,尤其是从小蕾期到大蕾期阶段,ogura不育系、改良萝卜不育系的IAA、GA和ZR含量都极显著低于保持系.IAA、GA和ZR是植物体内重要的信号物质,可调节植物的多种生命活动,其亏缺影响花粉的正常发育,从而引起败育.     

氢化可的松致雄大鼠骨质疏松症的骨计量学研究

实验用３月龄♂ＳＤ大鼠１６只，随机分为２组，Ａ组灌喂生理盐水２ｍｌ／ｋｇＢ组灌喂氢化可的松３．６ｍｇ／ｋｇ，６次／周，一个月后改为２次／周，３个月后用图像分析仪两组大鼠胫骨上段的骨片进行动态及静态测算和分析，结果显示，Ｂ组动态参数中代表成骨细胞形成和活性的荧光周长，矿化沉积率和骨形成率与Ａ组比较分别减少了４９％（Ｐ〈０．０１），２８％（Ｐ〈０．０１）和６３％（Ｐ〈０．０１），标志破骨细胞活性的骨吸     

GENESIS诱导小麦雄性不育与幼穗中乙烯含量的关系

在小麦发育的 Feekes8.5时期用化学杂交剂 GENESIS进行处理 ,分别在小麦花药发育的单核期、二核期和三核期测定幼穗中乙烯释放量的变化 ,研究 GENESIS诱导小麦雄性不育与乙烯的关系。结果表明 :经化学杂交剂 GENESIS诱导后 ,幼穗中乙烯释放量在 3个时期均明显高于对照。随着 GENESIS喷施剂量的增加 ,诱导小麦雄性不育率也相应增加 ,同时幼穗中乙烯释放量也表现出相同的增长趋势。表明 GENESIS诱导小麦雄性不育的生化机理在于 GENESIS诱导小麦幼穗中乙烯释放量增加 ,乙烯释放量的变化与小麦雄性不育有直接关系。同时 ,利用乙烯合成抑制剂 (AVG)处理细胞核质互作雄性不育系后 ,内源乙烯释放速率降低 ,育性得到部分恢复     

Naturally occurring antihormones: secretion of FSH antagonists by women treated with a GnRH analog

Follicle-stimulating hormone (FSH) is a glycoprotein essential for gonadal development and steroidogenesis. Recent studies suggest that deglycosylation of FSH results in the formation of antagonistic proteins that are capable of binding to gonadal receptors but that are devoid of bioactivity. Treatment of hypogonadal women with an antagonist of gonadotropin-releasing hormone substantially decreased serum FSH bioactivity with minimal changes in immunoreactivity. Chromatofocusing and size fractionation of the serum samples indicated the secretion of immunoreactive FSH isoforms that are devoid of bioactivity but that are capable of blocking FSH action in ovarian granulosa cells. These findings provide the first demonstration of naturally occurring circulating antihormones. These FSH antagonists may play an important role in the physiology and pathophysiology of the gonads.