单层培养的垂体生长激素分泌瘤细胞对生长激素释放激素和生长抑素的反应

本文研究7例肢端肥大症患者垂体单纯生长激素(GH)分泌瘤单层培养细胞对GH释放激素(GRF)和生长抑素(SS)的反应。培养液中10~(-8)M GRF使5例瘤细胞GH分泌增加171.6±22.6％,10~(-7) M GRF使全部7例瘤细胞GH分泌明显升高到220.6±47.7％。10~(-9)～10~(-7) M SS使5例瘤细胞GH基础分泌下降到50.4±9.8％。同时加入10~(-8)或10~(-7) M的GRF和SS,在7例瘤细胞上均看到GRF兴奋GH分泌的作用被完全阻断。3例病人术前接受GRF和SS试验,血清GH水平的变化分别为对照的222.0±30.6％和10.7±4.7％。结果表明单层培养的垂体GH瘤细胞对GRF和SS仍有反应。     

红景天素对老龄大鼠垂体生长激素细胞的影响

目的　探讨红景天素对老龄大鼠垂体生长激素细胞的影响。方法　采用放射免疫技术和体视学方法对老龄大鼠垂体生长激素的分泌量、垂体激素细胞的核质比和细胞核直径进行研究。结果　血液中生长激素含量 ,给药组 3 2 2 2± 0 576ng/ml,对照组2 0 4 8± 0 786ng/ml;生长激素细胞的核质比 ,给药组 1 0 70± 0 1 61 ,对照组 0 470± 0 0 57(P <0 0 1 ) ;生长激素细胞核直径 ,给药组 1 6 856± 1 0 98μm ,对照组 1 4 836± 1 0 39μm(P <0 0 5)。 结论　红景天素对老龄大鼠生长激素细胞的活性有明显的促进作用     

促生长素释放激素及细胞因子对垂体促生长素基因表达的 …

目的 研究人促生长素释放激素（ｈＳＲＨ）、白细胞介素－１β（ＩＬ－１β）、白细胞介素－６（ＩＬ－６）和肿瘤坏死因子－ａ（ＴＮＦ－ａ）对垂体前叶促生长素细胞中生和素基表达的调控作用及其与Ｐｉｔ－１的关系。方法 将含有人促生长素基因启动子和萤光素酶报告基因的融合基历表达质粒（ｐＧＬ２－ＧＨ－Ｌｕｃ）单独转染或与人Ｐｉｔ－１基因表达质粒（ＰｃＤＮＡ－Ｐｉｔ－ｌｃＤＮＡ）共转染于大鼠ＧＨ３细胞中,体外观察     

不同生长激素激发试验时矮小男童血浆胃促生长素水平

对30例矮小男童(20例GH缺乏症和10例特发性矮小症)在不同的激发试验各时间点采血,以放射免疫法测定血浆胃促生长素水平。结果显示,在精氨酸激发试验各时间点血浆胃促生长素水平差异有统计学意义,生长激素释放激素(GHRH)激发试验中血浆胃促生长素峰值与激发后GH峰值呈负相关(P<0.05)。     

促性腺激素释放激素类似物与生长激素联用治疗真性性早熟女孩的疗效评价

目的评价促性腺激素释放激素类似物(GnRHa)联用重组人生长激素(rhGH)治疗对于改善真性性早熟(CPP)女孩预测成年身高(PAH)的疗效。方法对已接受GnRHa治疗6个月以上、治疗中生长速度显著减慢至4cm/年以下的15例CPP女孩,予联用rhGH(1 U·kg~(-1)·w~(-1))治疗4个月以上(4～13个月),对联用rhGH前后的生长速度、按骨龄的身高标准差分值(HtSDS_(BA))以及PAH进行比较。结果联用rhGH后生长速度较联用前6个月显著加快[(7.4±1.7)cm/年vs (3.2±0.7)cm/年,P＜0.01]；其中7例联用rhGH 9个月以上者,联用第二个6个月的生长速度较第一个6个月[(6.5±1.0)cm/年vs (8.8±1.1)cm/年]稍减慢,但仍显著快于联用前[(3.2±0.8)cm/年]。经疗程较正,联用rhGH后的每半年HtSDS_(BA)的增加显著大于联用前[(0.35±0.15)vs(0.12±0.18),P＜0.01]；联用rhGH后每6个月的PAH改善亦较联用前[(3.2±1.4)cm vs(1.4±1.1)cm,P＜0.01]显著增加。结论联用rhGH能显著加快GnRHa治疗中生长过慢的真性性早熟女孩的生长速度,促进身高年龄对骨龄的追赶以及改善预测成年身高。     

TRH,IL—1β对大鼠垂体GH3细胞游离钙影响的体外研究

作者使用Fura-2作为Ca~( )指示剂,观察了促甲状腺激素释放激素(TRH)和白细胞介素-1β(IL—1β)对体外培养的大鼠GH_3垂体细胞内Ca~( )([Ca~( )]i)水平的影响。结果显示10~(-7)～10~(-9)mol/L浓度TRH促进[Ca~( )]i动员,其程度呈TRH剂量依赖性。单用0.01～10U/ml IL—1β未增加工[Ca~( )]i水平。用0.1U/ml IL—1β与待测细胞温育1和3分钟后,加入TRH,[Ca~( )]i释放则受明显抑制;而TRH与IL—1β同时使用,抑制作用则明显减弱。本研究证实[Ca~( )]i对TRH在垂体细胞内的作用起重要信息传递作用,一定剂量IL—1β可能通过抑制TRH诱导的[Ca~( )]i释放影响垂体功能。     

慢性氟中毒大鼠垂体生长激素细胞及下丘脑生长抑素神经元…

本实验对慢性氟中毒大鼠垂体生长激素（ＧＨ）细胞及下丘脑生长抑素（ＳＳ）神经元分析了免疫细胞化学染色，并用图像分析仪对ＧＨ及ＳＳ进行了半定量分析，结果表明：同对照组相比，氟中毒垂体ＧＨ细胞中的阳性反应颗粒细小并弥散地分布，半定量分析表明其ＧＨ含量明显低于对照组，未见下丘脑ＳＳ神经元及其ＳＳ含量有明显改变，本研究结果提示高氟可直接作用于垂体ＧＨ细胞影响其合成分泌功能。     

GRH调节的AC－cAMP系统对垂体生长激素瘤发病机制中的影响

在２１例体外培养的人生长激素（ＧＨ）瘤细胞研究了生长激素释放激素（ＧＲＨ）对细胞内ｃＡＭＰ水平与ＧＨ分泌的影响和腺苷酸环化酶－环磷酸腺苷（ＡＣ－ｃＡＭＰ）系统激动剂霍乱毒素（ＣＴ）、Ｆｏｒｓｋｏｌｉｎ和双丁酰ｃＡＭＰ（ｄｂｃＡＭＰ）对ＧＨ分泌的凋节作用及其相互关系。结果显示：分别有６１．９％（１３／２１）和５７．１／（１２／２１）的患者ＧＨ瘤细胞的ＧＨ分泌对ＧＲＨ和ＣＴ的刺激个敏感；而Ｆｏｒｓｋｏｌｉｎ和ｄｂｃＡＭＰ可使８８．９％（８／９）和１００％（５／５）患者的垂体瘤细胞ＧＨ分泌显著增加（Ｐ＜０．０５）；在９例瘤细胞中有４例ＧＲＨ可使细胞内ｃＡＭＰ水平升高至对照的１３４．２％～７２４．３％（Ｐ＜０．０５），在另５例ＧＲＨ对ｃＡＭＰ水平无影响。以上结果说明，多数ＧＨ瘤细胞存在着ＧＲＨ受体和（或）受体后鸟苷酸调节蛋白     

糖皮质激素联合生长激素对大鼠急性肝衰竭的保护作用及其机制初步探讨

目的研究糖皮质激素（氢化考的松琥珀酸钠,HCSS）联合生长激素（GH）对大鼠急性肝衰竭的影响.方法采用Wistar大鼠注射脂多糖（LPS）和D氨基半乳糖（D-GalN）制备急性肝衰竭模型,随机分为正常对照组、模型对照组、药物干预组及造模后4 h干预组,各组于末次给药6 h后处死大鼠,常规H-E染色观察大鼠肝脏病理变化,检测肝功能和血清TNF-α,IL-8,IL-6水平;分离培养大鼠库普否细胞（KC）,经LPS（10μg/ml）刺激,于刺激开始（0 h）和4 h后分别给药,并于0、2、4、8和24 h后收集上清,测定TNF-α.结果HCSS或HCSS联合GH预防给药可显著降低急性肝衰竭大鼠血清TBIL、ALT、AST和TNF-α、IL-8、IL-6水平,药物干预组较模型组肝细胞坏死有明显改善.LPS刺激2 h后,KC培养上清中TNF-α浓度开始上升并在4 h达高峰.在培养开始加用HCSS可明显降低TNF-α水平,而培养4 h后加用HCSS不能明显降低TNF-α水平.在培养开始加用GH可进一步升高TNF-α水平,而联合给予HCSS后可降低TNF-α水平.结论预防性给予大鼠药物干预可明显减轻肝损伤,而在造模4 h后使用HCSS则无明显效果.联合使用合理剂量的HCSS和GH仍能较好的减轻肝损伤.     

甲状腺功能低下大鼠生长激素细胞的超微结构

本文对甲低大鼠腺垂体生长激素细胞的超微结构进行了观察,并对其分泌颗粒进行了立体计量分(?)。结果表明,甲低大鼠生长激素细胞内质网扩张,线粒体肿大,分泌颗粒减少等改变。甲低大鼠分泌颗粒的 V_v、N_A、N_v 均明显低于对照组。     

人胎肝非实质间充质干细胞体外诱导分化为类肝细胞

目的体外诱导人胎肝非实质间充质干细胞(NPMSCs)分化为类肝细胞,对类肝细胞进行分子生物学及功能鉴定。方法采用体外细胞培养技术,分离培养人胎肝NPMSCs,在1%基质胶作基质,2.5 mmol/L氮胞苷预处理10～12 h,肝细胞生长因子10μg/L加成纤维细胞生长因子4 10μg/L加肝细胞生长培养基中诱导。用显微摄像和四甲基偶氮唑盐研究细胞增殖及生长特征,用流式细胞仪、免疫组织化学和逆转录聚合酶链反应鉴定细胞表型。采用酶联免疫吸附法检测培养上清液中人Alb水平,过碘酸希夫试验进行糖原染色。结果从人胎肝获得贴壁细胞种植后生长分裂良好,连续传10代后,每份人胎肝NPMSCs可扩增达109个细胞。NPMSCs表型为CD166阳性,CD34阴性。在添加成纤维细胞生长因子4和肝细胞生长因子的基质胶上诱导培养的NPMSCs在21～28 d时,形态由长梭形变为三角形、多角形或类圆形。细胞转圆率为40%,双核细胞比率5%。免疫组织化学和逆转录聚合酶链反应检测显示未诱导培养的NPMSCs中,有较少的细胞表达甲胎蛋白及其mRNA,未见其他肝脏特有的转录因子或者细胞质蛋白标志。诱导早期可见较多细胞表达GATA4、甲胎蛋白和CK18及其mRNA,至诱导后期表达下降,而Alb、CK18、谷胱甘肽S转移酶-π和肝细胞核因子1α表达逐渐上升。Alb、CK18阳性细胞比例达60%。未诱导分化的NPMSCs不分泌Alb,诱导分化的NPMSCs以时间依赖方式产生Alb。NPMSCs诱导14d时首先见到部分细胞出现红紫色染色的糖原积聚物,28 d后阳性染色细胞数量增多。结论在本实验诱导条件下可获得在复制及翻译各环节肝细胞标志阳性的类肝细胞。诱导后NPMSCs已具备肝细胞特有的功能性特征。     

Growth hormone and growth hormone secretagogue effects on nitrogen balance and urea synthesis in steroid treated rats

ObjectivesGrowth hormone (GH) reduces the catabolic side effects of steroid treatment via effects on the amino-nitrogen metabolism. Ipamorelin is a synthetic peptide with GH releasing properties. We wished to study the metabolic effects of Ipamorelin and GH on selected hepatic measures of α-amino-nitrogen conversion during steroid-induced catabolism.DesignFive groups of rats were included: (1) free-fed controls (2) pair-fed controls (3) prednisolone (delcortol, 4 mg × kg^?1 × day^?1) (4) prednisolone and GH (1 mg × kg^?1 × day^?1) (5) prednisolone and Ipamorelin (0.5 mg × kg^?1 × day^?1). After seven days the hepatic capacity of urea-N synthesis (CUNS) was determined in parallel with measurements of liver mRNA levels of urea cycle enzymes, whole-body N-balance, and N-contents of various organs.ResultsCompared to pair-fed controls, prednisolone increased CUNS (p < 0.01) as well as the expression of urea cycle genes (p < 0.01), and decreased N-balance (p < 0.01) as well as organ N-contents (p < 0.05). Compared to prednisolone treated animals, co-administration of GH reduced CUNS by 33% (p < 0.01), normalized urea cycle gene expression, improved N-balance 2.5-fold, and normalized or improved organ N-contents. In prednisolone treated rats Ipamorelin reduced CUNS by 20% (p < 0.05), decreased the expression of urea cycle enzymes, neutralised N-balance, and normalized or improved organ N-contents.ConclusionAccelerated nitrogen wasting in the liver and other organs caused by prednisolone treatment was counteracted by treatment with either GH or its secretagogue Ipamorelin, though at the doses given less efficiently by the latter. This functional study of animals confirms that the GH secretagogue exerts GH related metabolic effects and may be useful in the treatment of steroid-induced catabolism.     

丁酸钠诱导体外培养的大鼠肝卵圆细胞分化为成熟肝细胞

目的探讨分化刺激剂丁酸钠对体外培养的大鼠肝卵圆细胞分化的影响。方法从喂养含0．1%乙硫氨酸的胆碱缺乏性饮食4～6周的人鼠肝脏中分离出盱卵圆细胞,用免疫细胞化学和逆转录聚合酶链反应(RT-PCR)等方法对其进行鉴定。用0．75mmol/L酸钠处理大鼠肝卵圆细咆后．姬姆萨染色观察细胞表型改变,western blot检测细胞白蛋白的表达水平。结果免疫细胞化学结果显示分离出的细胞既表达成熟肝细咆的标志物白蛋白,也表达胆管细胞的标志物细胞角蛋白19,RT-PCR结果显示这些细胞还表达干细胞的标志物c-kit,但不表达造血干细胞的标志物CD34,表明这些细胞是大鼠肝前体细胞——肝卵圆细胞。0．75mmol/L丁酸钠能诱导大鼠肝卵圆细胞出现明显的表型改变,细胞变大,变圆,核浆比减小,且双核细胞数增多,约占总细胞数的50%左右,同时western blot的结果显示0．75mmol/L丁酸钠能够提高大鼠肝卵圆细胞白蛋白的表达水平。。结论分化刺激剂丁酸钠能诱导体外培养的大鼠肝卵圆细胞向成熟肝细胞分化。     

Differentiation of fetal liver cells in vitro.

Fetal mouse liver hepatocytes proliferate on a substrate of irradiated pigskin epidermis scored with scalpel blade slits to permit cell access to the basement membrane. At the time the cells are explanted, fetal genes, such as those responsible for production of alpha-fetoprotein (AFP) and gamma-glutamyltransferase (GGTase), are strongly expressed. The levels of GGTase decrease rapidly and become undetectable within 2 weeks. The levels of AFP decrease more gradually but become undetectable after 3-5 weeks in culture. As the AFP levels decrease, there is a concomitant increase in albumin production. Hydrocortisone prolongs production of AFP (for up to 8 weeks) but not of GGTase, and it decreases albumin production for up to 8 weeks. Once cells lose AFP expression, addition of hydrocortisone does not restart it. Based on these data, fetal mouse liver hepatocytes, cultured on pigskin, seem to be an excellent in vitro model for liver cell maturation.     

T3对体外培养的大鼠胚胎大脑神经细胞神经递质代谢的影响

本文采用无血清培养液(SFM),加入生理浓度的 T_3,观察 T_3对15—18天大鼠胚胎大脑神经细胞神经递质代谢的影响。发现 T_3能明显促进体外培养的胎鼠大脑神经细胞合成,分泌单胺类神经递质,促进神经细胞发育成熟。     

Differential secretion of chicken growth hormone variants after growth hormone-releasing hormone stimulation in vitro

Variants of growth hormone (GH) are present in most vertebrates. Chicken GH (cGH) undergoes posttranslational modifications that contribute to its structural diversity. Although the 22-kDa form of GH is the most abundant, some other variants have discrete bioactivities that may not be shared by others. The proportion of cGH variants changes during ontogeny, suggesting that they are regulated differentially. The effect of growth hormone-releasing hormone (GHRH) on the release of cGH variants was studied in both pituitary gland and primary cell cultures, employing sodium dodecyl sulfate polyacrylamide gel electrophoresis, Western blotting, and densitometry. GHRH (2 nM, 2 h) stimulated the secretion of most of the size variants of cGH although the amplitude of increase was not equal for each one. A differential effect on the secretion of GH size variants, particularly on the 22- (monomer) and 26-kDa (putatively glycosylated) cGH isoforms was found in both systems. In the whole pituitary culture, the proportion of the 26-kDa immunoreactive cGH increased 35% while the 22 kDa decreased 31% after GHRH treatment in comparison with the controls. In the primary cell culture system, the proportion of the glycosylated variant increased 43% whereas the monomer and the dimer decreased 22.26 and 29%, respectively, after GHRH stimulation. Activators of intracellular signals such as 1 mM 8-bromo-cAMP and 1 μM phorbol myristate acetate had a similar effect to that obtained with GHRH. The data support the hypothesis that GH variants may be under differential control and that GHRH promotes the release of a glycosylated cGH variant that has an extended half-life in circulation.     

5-氮胞苷诱导大鼠骨髓基质细胞表达β肾上腺素能受体的研究

目的 探讨5-氮胞苷对大鼠骨髓基质细胞β肾上腺素能受体(β受体)及其mRNA表达水平的影响。方法 体外分离培养大鼠骨髓基质细胞,以5-氮胞苷诱导24 h,正常培养3周,125I-Pindolol同位素放射配基法测定β受体密度,RT-PCR法测定其β受体mRNA表达水平,并与培养乳鼠心室肌细胞相比较。结果 正常培养大鼠骨髓基质细胞不表达β受体蛋白及其mRNA。5-氮胞苷诱导后的骨髓基质细胞表达β受体,随着5-氮胞苷浓度增加,骨髓基质细胞的β受体密度增加,至5×10-6mol/L时达最高峰;β受体密度随着培养时间延长而逐渐增加,于4周时接近正常心肌细胞水平。结论 5-氮胞苷诱导后,培养大鼠骨髓基质细胞表达β受体,并有明显的剂量和时间依赖性,分化后的细胞具有类似儿茶酚胺类激素的受体。