老年比格犬肝脏组织学与超微结构的变化  

Changes of the liver histology and ultrastructure in aged Beagle dogs

作　　者：张晓莉[1] 郑松柏[1] 李小雯[1] 肖立[2] 俞彰[3] 

机构地区：[1]复旦大学附属华东医院消化科,上海200040 [2]复旦大学附属华东医院病理科,上海200040 [3]复旦大学上海医学院电镜中心

出　　处：《中华消化杂志》2015年第6期395-400,共6页Chinese Journal of Digestion

摘　　要：目的研究老年比格犬肝脏的组织学与超微结构变化。方法将15只犬龄1．5～10．6岁的国际标准试验用健康比格犬，按犬龄分为中青年组和老年组。老年组7只，平均犬龄为（8．26±1．52）岁；中青年组8只，平均犬龄为（2．21±0．94）岁。予以静脉麻醉后取肝脏组织，HE染色后在光学显微镜下观察比较两组肝细胞数目、肝细胞形态及间质情况；在电子显微镜下观察比较两组肝细胞内线粒体数量密度、形态和面积分数，内质网形态和面积分数，微粒体数量密度和形态，肝血窦内皮细胞的厚度和窗孔密度（即单位长度窗孔的数目）和直径，脂褐素的形态和数量密度等。两组间比较采用独立样本的t检验。结果光学显微镜下观察，肝细胞围绕中央静脉呈放射状排列，尤以中青年组明显，肝细胞呈圆形或椭圆形，以单核或双核细胞居多，中青年组肝细胞胞质呈致密的淡红色，空泡状脂滴小而少见，细胞边界清楚；老年组肝细胞胞质空泡化明显，可见较大的空泡状脂滴，胞质内散在嗜酸性颗粒，细胞边界模糊，肝细胞数目较中青年组明显减少[（75．80±5．76）／高倍视野比（97．80±6．45）／高倍视野，t=-2．510，P=0．026]。中青年组及老年组比格犬肝组织内均未见明显炎性细胞浸润。老年组较中青年组细胞间隙增大、细胞外间质增多。电子显微镜下观察，正常肝细胞内线粒体呈双膜的椭圆形、圆形或马蹄状，其内可见嵴，主要分布在细胞核周围。与中青年组相比，老年组肝细胞内线粒体形态多变，线粒体数量密度较中青年组明显减少[（0．202±0．021）／μm^2比（0．248±0．040）／μm^2，t=2．683，P=0．020]，面积分数较中青年组明显减少（0．136±0．015比0．202±0．019，t=-6．083，P〈0．01）；内质网呈网状叠状排列，散在片状分布，细胞核周围较为多见，呈�Objective To investigate the changes of liver histology and ultrastructure in aged Beagles dogs. Methods A total of fifteen healthy Beagles, 1. 5 to 10. 6 years old, were divided into middle-aged group （n=8, average （2. 21±0.94） years old） and aged group （n=7, average （8.26±1.52） years old） according to age. After intravenous anesthesia, the liver tissues of dogs were taken to compare number and morphology of hepatocytes and extra cellular matrix （ECM） of two groups under light microscope with hematoxylin-eosin staining. The number density, morphology and area fraction of mitochondria, the morphology and area fraction of endoplasmic retieulum, the changes of number density and morphology of microbody, the thickness of hepatic sinusoidal endothelial cell as well as the density and the diameter of fenestrae, the changes of morphology and number of lipofuscin in two groups were compared under electron microscope. Independent sample t-test was performed for comparison between two groups. Results Under light microscope, hepatocytes were arranged radially around the central veins, especially obvious in the middle aged group, ttepatocytes were circular or oval, most were mononuclear or binuclear. The cytoplasma of hepatocyte in middle aged group was dense eosinophilic pink. Vacuolar lipid droplets were small and scanty. The cell boundary was clear. In aged group, cytoplasmic vacuolization of hepatocyte was more obvious, bigger vacuolated lipid droplets were observed, eosinophillic granules were scattered in the cytoplasma, cellular boundary was blurry and the number of hepatocytes significantly decreased when compared with middle-aged group （（ 75.80 ± 5. 76 ）/high power field （HPF） vs （97.80±6.45）/HPF, t=-2.510, P=0.026）. There were no obvious infiltration of inflammatory cells in the liver tissue of Beagles dogs in both middle-aged group and aged group. Compared with middle aged group, cell gap and ECM increased in aged group. Under electron microscope, mitochondria of normal hep

关 键 词：衰老 肝脏 组织学 超微结构 模型 动物 

分 类 号：R575[医药卫生—消化系统]