衰老时人大脑皮质超微结构的变化

用电子显微镜对10例正常老年人大脑额叶、顶叶和颞叶皮质进行了研究。发现神经元核内出现包含物,神经细胞和胶质细胞质内出现多形态的纤维性包含物,线粒体变性,胞质空泡化以及脂褐素体的沉积等。突触的变性发现为突触前、后末梢内线粒体变性,突触小泡的融合破坏。     

细辛对D-半乳糖所致衰老小鼠睾丸的形态学研究

本文研究了细辛对D－半乳糖所致衰老小鼠的抗衰老作用，应用光镜电镜技术测定小鼠睾丸的重量、生精小管直径、生精上皮细胞数、随龄变化的间质细胞数，同时观察了细辛对上述指标的影响。结果 1．随增龄、睾丸重量减轻，生精小管直径缩小。衰老时租精细胞缺如，仅有支持细胞或散在分布，间质细胞随龄递减。2．细辛可以使小鼠的曲细精管增粗，生精过程活跃，生精细胞增多，间质细胞增多。结论 细辛有一定抗衰老作用。     

D-半乳糖致衰老的研究进展

D-半乳糖衰老动物模型已成为国内较公认的衰老动物模型,与其它几种衰老动物模型如臭氧损伤衰老模型、去胸腺衰老模型、自然衰老模型等相比,该模V简便易行,价格低廉,因而得到广泛运用.本文拟从行为学水平,生化水平,组织病理学水平,分子生物学水平等方面对该模型进行综述.     

大鼠大脑中动脉超微结构的衰老性变化

目的 研究大脑中动脉超微结构的增龄变化，为探索脑血管疾病的发病机制提供参考资料。方法 应用透射电镜观察各年龄组大鼠大脑中动脉的超微结构。结果 老龄组大鼠大脑中动脉基膜增厚，内弹性膜变薄、不均质、边缘伸出分支到中膜，内皮细胞和平滑肌细胞向内弹性膜穿过，内弹性膜内出现脂质，并有分层、断裂现象，胶原纤维增多。结论 随着年龄的增加，大鼠大脑中动脉的超微结构具有明显的改变。     

中药麦冬对D-半乳糖衰老模型大鼠血液流变性的影响

目的研究麦冬对D -半乳糖衰老模型大鼠血液流变学的影响 ,筛选预防中风药物。方法用3月龄大鼠注射D -半乳糖做衰老模型 ,3月龄正常大鼠为青年对照组。用中药麦冬对模型大鼠进行治疗 ,6周后检测各组大鼠血液流变学指标。结果D -半乳糖模型大鼠全血和血浆粘度等指标明显升高 ,麦冬治疗组血液粘度升高不明显。结论中药麦冬具有降低D -半乳糖衰老大鼠血液粘度的作用     

D-半乳糖致衰老大鼠骨髓间充质干细胞的特性

目的:观察D-半乳糖致衰老大鼠骨髓来源的间充质干细胞的形态学及生物学改变.方法:选择SPF级雄性SD大鼠10只, 随机分为2组:青年对照组和衰老模型组.衰老模型组大鼠每天用D-半乳糖颈背部皮下注射, 剂量为400 mg/kg, 连续注射4个月.分别从青年对照组和衰老模型大鼠的骨髓中培养出间充质干细胞(BMSCs).倒置显微镜下观察细胞形态及生长情况, 流式细胞术(FCM)检测表面抗原, 比较两组原代细胞集落形成数量和增殖情况, 透射电镜下观察其形态和结构变化.结果:两组体外培养的原代和第3代骨髓间充质干细胞在形态上无差异,早期呈集落样生长.FCM检测显示, 两组BMSCs的免疫表型一致, CD29和CD44为阳性表达, CD34. 和CD45为阴性表达.两组细胞都具有成骨诱导和成脂诱导能力.与青年对照组相比, 衰老模型组BMSCs生长速度明显减慢, 集落形成能力明显地降低(P<0. 05).透射电镜观察发现, 衰老模型组BMSCs呈现衰老的 形态和结构变化, 核膜内折, 细胞质内存在大量空泡, 内质网和线粒体增大或肿胀.结论:大鼠骨髓间充质干细胞的增殖随年龄增长而降低;体外培养的衰老模型组骨髓间充质干细胞出现衰老征象.     

D-半乳糖诱导衰老高黏滞血症大鼠模型初探

目的探讨研制简便易行的衰老高黏滞血症(HVS)实验动物模型.方法将青年大鼠分为青年对照组、D-半乳糖致亚急性衰老模型1组、2组.分别在腹部皮下注射0.9%生理盐水、D-半乳糖于10周、6周、10周后以青年组大鼠为对照,观察血液流变性、血小板聚集、抗凝血酶Ⅲ(ATⅢ)活性,肝肾组织超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量等指标并做主动脉组织病理学检测.结果青年对照组的血浆黏度和SOD呈负相关、衰老模型两组的血浆黏度和SOD呈负相关;与青年组比较,衰老模型1、2组血液流变学的多项指标、血小板最大聚集率、肝肾组织MDA含量等明显增高,AT-Ⅲ活性及肝肾组织SOD活性明显降低,主动脉壁内膜增厚.结论D-半乳糖诱导的衰老大鼠模型具有与老年鼠相似的血液流变学的改变,可用作为衰老高黏滞血症(HVS)实验动物模型.     

细辛和杜仲合剂对D-半乳糖所致衰老小鼠睾丸的形态学研究

目的 本实验研究了细辛与杜仲合剂对D－半乳糖所致衰老小鼠的抗衰老作用。方法 应用光镜电镜技术测定小鼠睾丸的重量、生精小管直径、生精上皮细胞数、间质细胞数的随龄变化，同时观察了细辛、杜仲合剂对上述指标的影响。结果 1．随增龄，睾丸重量减轻，生精小管直径缩小。衰老时生精细胞缺如，仅剩支持细胞或见散在分布，间质细胞随龄递减。2．细辛与杜仲合剂具有一定的抗衰老作用，可以使小鼠的生精小管增粗，生精过程活跃，生精细胞增多，间质细胞增多。结论 细辛与杜仲合剂具有一定的抗衰老作用。     

大鼠胶质细胞参与D-半乳糖诱导脑衰老过程研究

目的:观察大鼠胶质细胞是否参与了D-半乳糖诱导的脑衰老的过程。方法:采用D-半乳糖制备动物大鼠衰老模型,生化分光光度法检测大鼠脑海马氧化应激水平,免疫组化方法观察大鼠海马星形胶质细胞和小胶质细胞的表达和形态变化。结果:大鼠模型组较对照组海马氧化应激水平增高,星形胶质细胞和小胶质细胞表达增多,染色增强。免疫荧光染色结果显示,模型组胶质细胞和诱导型一氧化氮合酶有共存关系,模型组海马一氧化氮水平升高。结论:大鼠胶质细胞可能参与了D-半乳糖诱导脑衰老的过程。     

当归多糖对D-半乳糖致衰老小鼠睾丸的保护作用

目的探讨当归多糖(ASP)对D-半乳糖(D-Gal)所致衰老小鼠睾丸的保护作用与机制。方法C57BL/6 J雄性小鼠40只,随机分为对照组、ASP对照组、衰老模型组ASP衰老模型组,每组10只。衰老模型组:小鼠颈背部皮下注射D-Gal(120 mg/kg,qd×42);对照组小鼠皮下注射等时与等量生理盐水; ASP对照组小鼠皮下注射等量生理盐水15 d,第16天开始腹腔注射ASP(140 mg/kg,qd×27); ASP衰老模型组小鼠建立方法同衰老模型组小鼠,第16天开始腹腔注射ASP(同ASP对照组)。模型复制完成第2天,采集各组小鼠内眦静脉血测定血清睾酮水平;取睾丸测定脏器指数;石蜡切片,HE染色观察睾丸组织学形态;做冷冻睾丸组织切片,衰老相关β-半乳糖苷酶(SA-β-Gal)染色观察睾丸组织细胞衰老情况;制备睾丸组织匀浆上清液,酶学法检测超氧化物歧化酶(SOD)活性,2,2’-连氮基-双-(3-乙基苯并二氢噻唑啉-6-磺酸)二铵盐(ABTS)法检测总抗氧化能力(T-AOC),硫代巴比妥酸法检测丙二醛(MDA)含量; Western blotting检测衰老相关蛋白P53、P21表达水平。结果各组间睾丸湿重及睾丸器官指数无明显差异,但衰老模型组小鼠睾丸组织结构损伤明显,生精小管的细胞层数减少,生精细胞出现退变,睾丸间质细胞明显减少;血清睾酮水平显著降低; SA-β-Gal染色阳性细胞密度显著增加;睾丸组织匀浆中SOD活性及T-AOC显著降低,MDA含量显著升高; P53、P21蛋白表达显著升高。与衰老模型组比较,注射ASP干预衰老过程,睾丸组织学结构损伤明显减轻,生精细胞退变与睾丸间质细胞减少均不明显;血清睾酮水平降低不明显; SA-β-Gal染色阳性细胞密度减少; SOD活性和T-AOC增高,MDA含量降低; P53、P21蛋白表达显著降低。结论 ASP具有拮抗致衰剂Dgal对睾丸的损伤作用,其机制可能与ASP抑制氧化应激损伤及抑制衰老相关基因表达有关。     

大鼠心肌细胞超微结构的增龄变化

目的：探讨心肌细胞超微结构增龄变化的规律。方法：取健康雄性大鼠，电镜观测左心房和左心室细胞超微结构的形态和定量变化。结果：随年龄增长，心房肌节长度、线粒体数量各年龄段间无差异，心室肌节长度、线粒体数量各年龄段间存在显著差异；闰盘逐渐典型、复杂；心房中心钠素颗粒不断增多。结论：心房肌节长度、线粒体数量一生中基本不变；幼年到青年为心室肌节和线粒体迅速发育期；心室肌原纤维增长既有肌节数目增多，又有肌节长度增加。     

大鼠坐骨神经超微结构的老年性变化

为了研究老年大鼠坐骨神经超微结构特点,随机取3月龄(成年组)和24月(老年组)龄正常SD大鼠各10只,用电镜观察两组间坐骨神经超微结构的差异。结果显示:老年组大鼠坐骨神经内有髓纤维的百分比、轴突间胶原纤维密度以及Schwann细胞胞质中脂褐质沉积密度均多于成年组(P<0.05);但无髓纤维之百分比少于成年组(P<0.05)。上述结果提示坐骨神经内的有髓纤维与无髓纤维百分比、轴突间胶原纤维密度以及Schwann细胞胞质中脂褐质沉积密度是衡量大鼠坐骨神经老化的形态标志之一。     

Seasonal changes in the hypothalamo‐pituitary‐testes axis of the japanese wood mouse (Apodemus speciosus)

Seasonal changes in the hypothalamo‐pituitary‐testes axis of the Japanese wood mice (Apodemus speciosus) were studied. The testes, epididymis, pituitary and hypothalamus were compared between mice in the breeding season (July) and non‐breeding season (October) using morphological techniques, and the plasma testosterone level was evaluated by enzyme immunoassay. Significant differences in these tissues were observed between the breeding season and the non‐breeding season. Specifically, differences in the non‐breeding season included 1) a decline in testicular and epididymal weights, arrest of spermatogenesis and decrease of serum testosterone concentration; 2) a decrease in the number of luteinizing hormone (LH)‐, follicle stimulating hormone (FSH)‐, prolactin (PRL)‐, and growth hormone (GH)‐immunoreactive cells, and decrease in the size of FSH, PRL, and GH‐immunoreactive cells; and 3) an increase in the size of gonadotropin‐releasing hormone (GnRH)‐immunoreactive neurons. Our findings indicate that the male adult Japanese wood mouse exhibits unique seasonal changes in the hypothalamo‐pituitary‐testes axis which are not found in laboratory mice. Anat Rec 260:366–372, 2000. © 2000 Wiley‐Liss, Inc.     

Ultrastructural Morphology of Folliculo-Stellate Cells in Human Pituitary Adenomas

Fifty-six pituitary adenomas were studied by electron microscopy in a search for the presence of folliculo-stellate cells (FSCs) with the aim of evaluating their prevalence and ultrastructural morphology. FSCs were scattered in two adenomas (one oncocytoma and one densely granulated GH cell adenoma) and were numerous in a sparsely granulated GH cell adenoma; their overall prevalence was 5.4%. Ultrastructural examination of the three neoplasms revealed that FSCs were hypertrophic element with abundant cytoplasm and organelles (in contrast to FSCs of the normal pituitary) and no obvious signs of neoplastic transformation. Junctional complexes between FSCs were similar to those described in the normal gland. Numerous follicular structures were lined by FSCs. FSCs in pituitary adenomas are probably nonneoplastic, reactive cells showing signs of hyperactivity, similar to FSCs found during pituitary hypersecretion and in estrogen-induced tumor.     

Morphological characteristics of myocardial remodeling during compensatory hypertrophy in aging Wistar rats

Remodeling of the myocardium in Wistar rats during aging is characterized by cardiomyocyte hypertrophy and increase of their total volume in the left ventricle; the total volume of the connective tissue also increases without marked changes in cardiomyocyte count and total volume of blood capillaries. The number of cardiomyocytes with contracture injuries of different severity in the myocardium of aging animals increases against the background of hemodynamic disorders. At the cellular level, compensatory hypertrophy of cardiomyocytes during aging is characterized by a pronounced increase in the myofibril bulk paralleled by relative deficiency of the mitochondria and pronounced deficiency of agranular sarcoplasmic reticulum and T system, involved in the regulation of intracellular Ca²⁺.     

Serotonin concentration in the hypothalamus during changes in pituitary thyrotropic function

The serotonin concentration in the hypothalamus was determined in sexually mature male rabbits during changes in pituitary thyrotropic function. No clear parallel was observed between the intensity of the pituitary thyrotropic function and the hypothalamic serotonin concentration. Stimulation of pituitary thyrotropic function by injection of 6-methylthiouracil or by partial thyroidectomy was accompanied by an increase in the serotonin concentration, whereas during aseptic inflammation in the thyroid gland or after a combination of removal of the superior cervical sympathetic ganglia and administration of chlorpromazine, the increase in thyrotropic function occurred without any significant changes in the hypothalamic serotonin concentration.Presented by Academician of the Academy of Medical Sciences of the USSR L. T. Malaya.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 7, pp. 772–774, July, 1976.