高正加速度环境对猴舌横纹肌c-fos基因表达的影响

目的 探索高正加速度( Gx)环境是否造成舌肌病理性损伤.方法 以9只雄性猕猴为对象,按受试Gx环境及持续时间随机分4组,对照组为 1Gx、300 s;实验组为3组,分别为 15Gx、200 s; 18Gx、165 s; 21Gx、140 s.采用病理学和免疫组织化学方法,观察模拟高正加速度环境下猴舌横纹肌肌细胞组织及c-fos基因表达的变化.结果 组织病理学观察:实验组和对照组猴舌横纹肌细胞无明显变化;免疫组织化学观察:对照组舌横纹肌细胞膜c-fos呈弱阳性表达,而细胞浆着色不明显.实验组舌横纹肌细胞膜、细胞浆c-fos着色明显,呈强阳性表达,不同高 Gx组之间无明显差别.结论 高于 15Gx的模拟正加速度环境可引起猴舌横纹肌细胞c-fos基因表达增强.     

电磁脉冲辐射对原癌基因c-fos调控区的影响

目的　通过研究电磁脉冲 (electromagneticpulse ,EMP)辐射对原癌基因c fos调控区域的影响 ,探讨其诱导细胞功能改变的机制。方法　构建c fos启动区氯霉素乙酰化转移酶 (chloramphenicolacetyl transferase,CAT) ,然后转染HeLa癌细胞株 ,高场强EMP模拟源 (有界波模拟源 )辐射细胞 ,EMP场强为6× 10 4V/m ,脉冲上升时间为 2 0ns ,脉宽为 3 0 μs ,频率为 2 .5个脉冲 /min ,辐射 2min ,处理后 2 0min时观察细胞中CAT的活性。结果　EMP辐射转染的细胞后 2 0min ,转染了P50 0 ( -711～ -2 2 3bp)和P2 50 ( -3 62～-10 0 )的Hela细胞其CAT活性明显高于对照水平的活性 (P <0 .0 1)。结论　EMP辐射可引起c fos基因调控区的 -3 62～ -2 2 5明显改变。     

内脏不适与甜味刺激对大鼠孤束核神经元激活的相互作用

目的观察内脏不适刺激和甜味觉刺激单独给予和先后联合给予对脑干孤束核(nucleustractussolitarius,NTS)中相关神经元的激活作用,为内脏感觉和味觉在NTS中的信息处理提供形态学方面的资料。方法SD雄性大鼠16只,以抽签法随机分为4组,分别给予4种不同方式的刺激,即处理组T1:胃内灌注LiCl+口内灌注糖精(I/GLiCl+I/OSac);T2:胃内灌注LiCl+口内灌注蒸馏水(I/GLiCl+I/OWater);T3:胃内灌注蒸馏水+口内灌注糖精(I/GWater+I/OSac);对照组C4:胃内灌注蒸馏水+口内灌注蒸馏水(I/GWater+I/OWater)。应用免疫组织化学方法观察刺激后大鼠孤束核吻尾方向上不同区域的FOS蛋白表达情况。结果与对照组C4相比,T1组大鼠在孤束核吻尾方向上5个区域的FOS蛋白表达增加(P1=0.001,P2=0.000,P3=0.000,P4=0.002,P5=0.002);T2组(P1=0.049,P2=0.001,P3=0.021;P4=0.002;P5=0.001)和T3组(P1=0.005,P2=0.000,P3=0.031,P4=0.002,P5=0.000)在这些区域的FOS蛋白表达也增加。两者联合刺激对孤束核尾侧最后区周围的内脏亚核(N2)和吻侧的味觉区(N4,N5)的FOS蛋白表达有交互作用(分别为F2=11.87,P2<0.01;F4=6.83,P4<0.05;F5=12.81,P5<0.01)。结论不适内脏刺激和甜味觉刺激对孤束核相关神经元的激活具有交互抑制作用。     

CGRP release and c-fos expression within trigeminal nucleus caudalis of the rat following glyceryltrinitrate infusion

Neuropeptide release and the expression of c-fos like immunoreactivity (c-fos LI) within trigeminal nucleus caudalis neurons (TNC) are activation markers of the trigeminal nerve system. Glyceryltrinitrate (GTN) is believed to stimulate the trigeminal nerve system, thereby causing headache. We examined the effects of a 30 min NO-donor infusion on CGRP release in jugular vein blood and c-fos LI within TNC of the rat. GTN (2 and 50 microg/kg/min) or NONOate infusion (25 nmol/kg/min) did not cause any CGRP release during and shortly after infusion, whereas administration of capsaicin resulted in strongly increased CGRP levels. GTN infusion (2 microg/kg/min for 30 min) did not lead to enhanced c-fos LI after 2 h and 4 h, whereas capsaicin infusion caused a time- and dose-dependent expression of c-fos LI within laminae I and II of the TNC. Surprisingly, GTN attenuated capsaicin-induced c-fos expression by 64%. The nitric oxide synthase (NOS) inhibitor L-NAME (5 and 50 mg/kg) reduced capsaicin-induced c-fos LI dose dependently (reduction by 13% and 59%). We conclude that GTN may lead to headaches by mechanisms independent of CGRP release from trigeminal nerve fibres. GTN doses comparable to those used in humans did not activate or sensitize the trigeminal nerve system. Both GTN and L-NAME reduced capsaicin-induced c-fos LI. This is most likely due to a feedback inhibition of nitric oxide synthases, which indicates that the c-fos response to capsaicin within TNC is mediated by NO dependent mechanisms.     

亮氨酸脑啡肽抑制血管平滑肌细胞增殖和c-fos基因表达

为探讨脑啡肽与去甲肾上腺素一起参与血管运动的局部调节机制，用MTT法、氚标胸腺嘧啶脱氧核苷掺入法和斑点杂交技术发现亮氨酸脑啡肽可抑制SD大鼠胸主动脉平滑肌细胞的增殖、DNA合成和c-fos基因的表达；阿片受体阻断剂纳洛酮无上述抑制作用，但可拮抗亮氨酸脑啡肽的上述抑制作用；上述作用还可被去甲肾上腺素所拮抗。结果提示，脑啡肽通过影响血管平滑肌细胞功能来参与血管运动的局部调节，这种调节可能是通过阿片受体介导的。     

姜辣素对顺铂致大鼠异嗜模型行为的作用

目的研究姜辣素对顺铂所致大鼠异嗜高岭土模型的影响并观察外周和中枢c-fos蛋白的表达。方法大鼠随机分成正常对照组、模型组、昂丹司琼+地塞米松组、阿瑞吡坦+地塞米松组、姜辣素组及姜辣素+地塞米松组,24 h及72 h记录各组摄食量及食高岭土量。免疫组化方法观察脑和回肠中c-fos蛋白的表达。结果 24 h内,姜辣素组、姜辣素+地塞米松组摄食量增加,啃食高岭土量减少,姜辣素组与姜辣素+地塞米松组相比摄食量增加(P<0.05);48～72h内,姜辣素组食高岭土量减少(P<0.05)。姜辣素组、姜辣素+地塞米松组c-fos阳性表达颗粒的灰度值明显高于模型组(P<0.05)。结论姜辣素可促进摄食并可抑制顺铂所致的大鼠异嗜高岭土行为,地塞米松对姜辣素无辅助作用。     

Enhanced Fos expression in rat lumbar spinal cord cultured with cerebrospinal fluid from patients with amyotrophic lateral sclerosis

Abstract

School, Okayama, Japan The etiology of amyotrophic lateral sclerosis (ALS) remains unknown although an existence of neurotoxic substances in cerebrospinal fluid (CSF) from ALS patients have been postulated. In order to investigate a possible effect of CSF from ALS patients on cellular signaling in spinal neurons, we compared Fos-like immunoreactivity (Fos-LI) in organotypic cultures of rat lumbar spinal cord after addition of CSF from ALS patients or another neurologic disease. Fos-LI was normally present predominantly in dorsal horn neurons, whereas only a few ventral horn neurons were positive for Fos-LI. The number of Fos-LI positive neurons significantly increased in dorsal horn with addition of CSF from ALS patients as well as glutamate at 100 μM. However, the increase was not observed with addition of CSF from other neurologic diseases. The increase in Fos-LI positive neurons in dorsal horn was reversed by a further supplement of MK801, an N-methyl-D-aspartate (NMDA) receptor antagonist, but not of CNQX, an a-amino-3-hydroxy-5-methyl-4- isoxazole propionic acid (AMPA)/kainate antagonist. These results indicate that there may be substances in CSF from ALS patients that stimulate Fos expression in certain populations of spinal neurons via the NMDA receptors. [Neurol Res 1999; 21: 309-312]     

胆固醇对大鼠心脏成纤维细胞增殖的影响

目的 :研究胆固醇 （CL）对大鼠心脏成纤维细胞增殖的影响 ,并对其机制进行探讨。方法 :分离、纯化、培养乳鼠心脏成纤维细胞 ,完全随机分为 3组 :对照组、中浓度胆固醇组 （0 .5g/L）和高浓度胆固醇组 （1.2g/L）。以3 H TdR掺入法测定各组细胞的增殖情况 ,并以流式细胞仪 （FCM）测定细胞周期。采用免疫组织化学染色方法观察各组c fos的表达情况。结果 :中浓度CL可使培养的乳鼠心脏成纤维细胞3 H TdR掺入量显著升高 （P <0 .0 5vs对照组 ） ,流式细胞仪检测表现为S期细胞明显增多。高浓度CL则抑制细胞生长 ,3 H TdR掺入量显著降低 （P <0 .0 5vs对照组 ） ,S期细胞数明显减少。同时中浓度CL显著升高Fos样免疫阳性细胞数及染色强度 （P <0 .0 5vs对照组 ）。结论 :中等浓度胆固醇可促进大鼠心脏成纤维细胞增殖 ,其机制可能与影响细胞内c fos基因的表达有关。