A sperm GPI-anchored protein elicits sperm-cumulus cross-talk leading to the acrosome reaction

The acrosome reaction has long been thought to be induced by the zona pellucida. Here we report the identification and function of a novel human sperm glycosylphosphatidylinositol (GPI)-anchored membrane protein, NYD-SP8. The release of the protein during sperm-egg interaction and its binding to the cumulus, the first layer of egg investment, elicits cross-talk between the gametes and produces calcium dependant release of progesterone, which lead to the acrosome reaction. An in vivo mouse model of NYD-SP8 immunization is also established showing a reduced fertility rate. Thus, contrary to accepted dogma, our study demonstrates for the first time that, prior to reaching the zona pellucida, sperm may release a surface protein that acts on the cumulus cells leading to the acrosome reaction, which may be important for determining the outcome of fertilization. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Received 11 August 2008; received after revision 18 December 2008; accepted 22 December 2008     

Opposite actions of testosterone and progesterone on UCP1 mRNA expression in cultured brown adipocytes

The brown adipose tissue (BAT) thermogenic response to diet-induced obesity and cold has been found to be gender dependent. In the present work, we aimed to investigate the effects of the main physiological male and female sex hormones, i.e. testosterone, progesterone and 17-β-estradiol, on the expression of uncoupling protein 1 (UCP1) – the main mediator of BAT thermogenesis – and on UCP2 and lipid accumulation in rodent brown adipocytes differentiated in culture. Testosterone-treated cells showed fewer and smaller lipid droplets than control cells and a dose-dependent inhibition of UCP1 mRNA expression, under adrenergic stimulation by norepinephrine (NE). These effects were reverted by the androgen receptor antagonist flutamide, suggesting they are dependent, at least in part, on the androgen receptor. Progesterone- and 17-β-estradiol-treated cells showed more and larger lipid droplets and progesterone stimulated NE-induced UCP1 mRNA expression at the lower concentration tested, but not at higher concentrations, suggesting that for brown adipocytes, this hormone is dose dependent. 17-β-Estradiol did not have any remarkable effect either on UCP1 or UCP2 mRNA expression. Interestingly, the specific progesterone receptor antagonist RU486 induced UCP1 and UCP2 mRNAs, including UCP1 mRNA expression in non-NE-treated brown adipocytes, suggesting a profound effect of this anti-progestagen on brown adipocyte thermogenic capacity. Thus, are conclude that testosterone, 17-β-estradiol, progesterone and RU486 have distinct actions on brown adipocytes, thus modulating UCP1 and UCP2 mRNA expression and/or lipid accumulation, and that sex hormones are factors that may explain in part the gender-dependent BAT thermogenic response. Received 24 June 2002; received after revision 20 August 2002; accepted 26 August 2002 RID="*" ID="*"Corresponding author.     

孕激素对应激性胃溃疡的保护和治疗作用

目的：探讨孕激素对应激性胃溃疡的保护和治疗作用．方法州、鼠分组。注射生理盐水及不同剂量的孕激素后，束缚加冷水刺激，计算溃疡指数及测定胃酸的pH值；束缚加冷水刺激后，注射生理盐水及孕激素，于应激后即刻、应激后5h、应激后7h计算溃疡指数．结果发现应激前注射孕激素对胃溃疡有明显的预防和保护作用；而溃疡发生后，注射孕激素有较好的治疗作用．     

过期妊娠产妇外周血和羊水雌二醇及孕酮水平的测定

目的 :测定过期妊娠产妇外周血血清和羊水中的雌二醇 (E2 )、孕酮 (P4 )水平 ,探讨E2 、P4水平变化与过期妊娠及宫缩发动的相关性。方法 :放射免疫法测定过期妊娠与足月妊娠产妇 (各2 0例 )羊水和外周血血清E2 、P4 浓度。结果 :1)过期妊娠组产妇外周血血清和羊水P4 水平明显高于足月妊娠组 (2 0 4 13± 4 1 16vs 176 4 6± 2 4 89,t =2 5 86 ,P <0 0 5 ;10 7 0 6± 2 8 6 6vs 71 2 3±13 6 7,t=5 0 4 6 ,P <0 0 1) ,E2 /P4 值明显低于足月妊娠组 (0 78± 0 17vs 0 90± 0 16 ,t=- 2 2 4 7,P<0 0 5 ;0 19± 0 10vs 0 2 6± 0 0 6 ,t=- 2 5 5 2 ,P <0 0 5 ) ,差异有显著性。 2 )临产组与未临产组产妇外周血血清中E2 、P4 水平及E2 /P4 值均无明显差异 (147 98± 12 0 0vs 16 2 0 5± 2 8 38,t =-1 76 2 ,P >0 0 5 ;175 0 2± 2 2 84vs 198 5 2± 4 0 0 8,t =- 2 0 17,P >0 0 5 ;0 88± 0 18vs 0 82±0 17,t=1 136 ,P >0 0 5 ) ;而临产组羊水中的P4 水平低于未临产组 (74 39± 16 73vs 97 0 9± 30 77,t=- 2 5 5 4 ,P <0 0 5 ) ,E2 /P4 值高于未临产组 (0 2 9± 0 0 9vs0 18± 0 0 6 ,t=- 4 4 41,P <0     

Membrane permeability changes duringRana oocyte maturation

A transition from an open system to a closed one must occur during the complex process of meiotic maturation of the amphibian oocyte. Membrane permeability to urea inRana oocytes following progesterone stimulation was determined, and the largest decrease was found to coincide with germinal vesicle breakdown. These findings suggest that the timing of the disappearance of membrane permeability correlates with developmental events that prepare the oocyte for a hostile environment.     

Ovarian stimulation by exogenous gonadotrophins in fetal ethanol-exposed immature rats

Summary Adult pregnant rats were given either an ad libitum liquid diet containing 5% ethanol, a pair fed liquid diet or an ad libitum diet of rat chow and water administered throughout pregnancy and during the nursing period. The female offspring received either pregnant mare's serum gonadotrophin (PMSG) or PMSG followed by human chorionic gonadotrophin (hCG) at 30 days of age. The ovaries of fetal ethanol-exposed animals responded greater to the exogeneous gonadotrophins with enhanced ovarian weights, increased numbers of ova shed, greater numbers of corpora lutea and antral follicles, and higher serum progesterone levels than in animals exposed to the control diets during gestation.     

Effects of female sex hormones on polyamine-oxidizing enzyme activities and polyamine concentrations in immature rat uterus and liver

17-estradiol (E₂) and progesterone (P) treatment of immature female rats (10 g/100 g body weight) respectively resulted in 1.38-fold (p<0.02) and 1.42-fold (p<0.02) increase in the uterine polyamine oxidase activity, and 2.45-fold (p<0.001) and 1.43-fold (p<0.02) increase in the uterine diamine oxidase activity, as compared to the controls. E₂ caused a 5-fold (p<0.05) and a 1.36-fold (p<0.05) increase in putrescine and spermidine concentration respectively in rat uterus. Increases of 1.7-fold (p<0.02) and 1.6-fold (p<0.05) in putrescine and spermine concentration were determined in the P-treated uterus, as compared to the controls. The spermidine/spermine ratio, which is regarded as an index of growth rate, was higher in the E₂-treated uterus and lower in the P-treated uterus than in the control uterus. No statistically significant hormonal effects were estimated in the immature liver. The data reported suggest the possibility of an involvement of polyamine-oxidizing enzymes in the modulation of polyamine concentrations in rat uterus by the female sex hormones.     

拟穴青蟹视神经节孕酮受体的免疫识别

研究表明,在甲壳类中可能存在类固醇的调控系统,然而核受体在进化的过程中是否依赖配体作用一直存在着争论.应用免疫印迹和免疫组织化学方法对拟穴青蟹(Scylla paramamosain)视神经节孕酮受体(PR)进行免疫识别.结果发现,拟穴青蟹视神经节中存在PR免疫阳性反应;其分子量约为70 ku,该物质广泛分布于视神经节的神经细胞核内.PR在拟穴青蟹视神经节的发现暗示着其类似于脊椎动物调节机制的存在;PR在神经细胞核中的定位表明其为核受体,很有可能在基因水平上参与拟穴青蟹视神经节的生理活动调节.     

类固醇激素对雌性实验鼠攻击行为的调节

通过分析讨论大鼠、小鼠的母性攻击行为和激素在怀孕、分娩、哺乳三个时期的变化、母性攻击行为的变化与激素水平变化之间的关系以及激素对母性攻击行为的调控 ,探讨激素对母性攻击行为的调节 .     

杂色曲霉转化孕酮的研究

利用杂色曲霉对孕酮进行生物转化,通过HPLC对转化产物进行检测,硅胶柱层析分离纯化转化产物,得到3个转化产物.运用NMR、MS、IR等波谱数据对转化产物进行结构鉴定,确定转化产物结构为:雄烯二酮(AD);睾酮;雄二烯二酮(ADD).研究结果表明,杂色曲霉菌株能够裂解孕酮C-17位的侧链,生成19个碳的转化产物,并对裂解产物进行结构修饰.