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981.
M.-N. Horcajada-Molteni M.-J. Davicco H. Collignon P. Lebecque V. Coxam J.-P. Barlet 《European journal of applied physiology and occupational physiology》1999,80(4):344-352
This experiment was performed to study the effects on femoral bone of endurance training performed during the 3 months before orchidectomy in rats which were then killed 90 days later. A total of 70 male Wistar rats were used at 8 weeks old. One day 0 of the experiment, 10 rats were killed by cervical dislocation and used as first controls. Among the 60 others, 30 were selected for treadmill running (60% maximal oxygen uptake, 1 h x day(-1), 6 days x week(-1) for 90 days). The 30 other rats remained at rest. On day 90, 10 exercised (IE) and resting (IR) rats were killed and used as intermediary controls. Among the 20 other animals of each group, 10 were surgically castrated (CXE, CXR) or 10 sham-operated (SHE, SHR) and killed on day 180. On day 90 femoral failure load (three-point bending test) was greater in IE than in IR. Simultaneously, the deoxypyridinolinuria was lower in IE than in IR. On day 180, femoral bones were thinner in CXR than in CXE. The lowest values for trabecular bone are in the distal femoral metaphysis were measured in CXE and CXR rats, but the value measured in CXE was no different from that measured in SHR. Simultaneously total femoral bone density was lower in CXR than in SHE, while no difference concerning femoral metaphyseal density was observed between CXE and SHR. These results confirmed that endurance running increased femoral bone growth and modelling and femoral trabecular area, and thereby peak bone mass, in 8-month-old male rats. In resting animals, castrated after the training period, androgen deficiency decreased femoral density, mineral content and trabecular area. This decrease was not observed in castrated but previously exercised rats. Thus, by increasing peak bone mass, it was considered that endurance training may have a preventive effect against orchidectomy-induced bone loss. 相似文献
982.
Immunfluorescence study of neuropeptides in identified neurons of the rat auditory superior olivary complex 总被引:2,自引:0,他引:2
S. Reuss Ursula Disque-Kaiser Sheila De Liz Marco Ruffer Randolf Riemann 《Cell and tissue research》1999,297(1):13-21
The present study was conducted to investigate the distribution and immunohistochemical characteristics of ascending and
descending projection neurons of the rat superior olivary complex (SOC), a group of interrelated brainstem nuclei. Ascending
neurons were identified by injection of cholera toxin B subunit (CTB) into the central nucleus of the inferior colliculus
(IC), descending neurons were labeled by application of Fluoro-Gold (FG) into the scala tympani of the cochlea, ipsilaterally
to the IC injection. In accordance with the literature, we observed neurons innervating the IC located in the lateral superior
olivary nucleus (LSO) and dorsal periolivary groups (DPO) on both sides, in the superior paraolivary nucleus (SPO) predominantly
ipsilateral, as well as in the ipsilateral medial superior olivary nucleus (MSO) and the medial nucleus of the trapezoid body
(MNTB). Cochlear projection neurons were found predominantly in the ipsilateral LSO as well as in the bilateral SPO, DPO,
MSO and MNTB. In addition, a considerable population of neurons in the ipsilateral LSO and SPO were identified as being both
ascending and descending. To further characterize these double-projecting neurons, brainstem sections were incubated in antisera
directed against different neuroactive substances. The majority of ascending/descending cells in the LSO contained calcitonin
gene-related peptide, but not substance P (SP), met-enkephalin (ENK) or tyrosine hydroxylase (TH). Some of these neurons apparently
were contacted by ENK- or SP-immunoreactive fibers and terminals. In addition, we found TH-immunoreactive neurons in the lateral
MNTB region. These neurons, which were labeled upon tracer injection into the cochlea (but not upon IC injection), probably
belong to the C1 catecholaminergic cell group and may represent a division of the uncrossed olivocochlear bundle. The present
results reveal the existence of a previously unknown subpopulation of SOC neurons that project to both the cochlea and the
inferior colliculus. Their CGRP immunoreactivity and their uncrossed projection pattern provide evidence that they may belong
to the cholinergic, putatively excitatory cell group.
Received: 4 January 1999 / Accepted: 17 February 1999 相似文献
983.
984.
地塞米松、噻庚啶和山莨菪碱对LPS诱导大鼠肝脏TNFα表达的影响 总被引:1,自引:0,他引:1
地塞米松(Dex)、噻庚啶(Cyp) 和山莨菪碱(Ani) 对脂多糖(LPS) 诱导的大鼠肝脏TNFα表达的影响。Wistar大鼠40 只, 静脉注射LPS(EcoliO111B4 5m g/kg) 后, 立即静脉给予Dex 5m g/kg、Cyp5m g/kg 或Am i10m g/kg,于LPS攻击后2h 取动物的肝脏,APAAP法进行TNFα免疫组织化学研究,North-ern 杂交分析TNFαm RNA 表达水平。结果发现LPS攻击后2h, 肝脏TNFαm RNA 表达水平显著增高, 肝脏枯否氏细胞胞浆内有大量的TNFα红染颗粒。Dex、Cyp 或Ani均能显著降低大鼠肝脏TNFαm RNA 水平和TNFα含量。结果表明Dex、Cyp 和Ani均显著抑制LPS诱导的TNFα基因表达, 可能有抗感染性休克作用。 相似文献
985.
局灶性脑缺血再灌损伤时神经细胞内Ca~(2+)时空动态变化的实验研究 总被引:4,自引:0,他引:4
本文用插线法制作局灶性脑缺血/再灌损伤模型,利用激光共聚焦扫描显微镜观察活体脑片细胞内Ca2+的分布及动态变化,结果表明:(1)缺血/再灌时间不同,梗塞面积不同,缺血4小时梗塞面积占同侧半球的16.3%,缺血4小时再灌20小时梗塞面积增加到25.9%,缺血24小时梗塞面积占同侧半球的60.4%。(2)本文首次观察到在缺血4小时纹状体区域的Ca2+变化明显高于皮层,并且再灌后皮层及纹状体区域Ca2+的含量明显增加 相似文献
986.
实验性脾虚证大鼠内分泌腺形态学与细胞化学研究 总被引:3,自引:0,他引:3
成年Wistar大鼠20只,分对照组和实验组。实验组用大黄煎剂灌服42天致实验性脾虚证。对两组睾丸,肾上腺和甲状腺进行常规形态学与细胞化学观察。形态学显示:睾丸,肾上腺和甲状腺的组织和细胞均有不同程度的损伤。细胞化学显示:各内分泌腺均表现酸性磷酸酶(ACP)减弱,个别内分泌腺细胞显示琥珀酸脱氢酶(SDH),三磷酸腺苷酶(ATPase)和PAS反应的变化。结果证明脾虚证不仅消化系统功能低下,而且内分泌功能也受到了影响 相似文献
987.
本实验通过对大鼠反复4次缺氧5min(常压,氧浓度10±0.5%)的缺氧预处理与经典的缺血预处理(Mury法)的对比观察表明,两者均能明显降低心肌丙二醛含量和肌酸激酶的漏出,提高心肌超氧化物岐化酶,Ca2+Mg2+-ATPase、细胞色素氧化酶、琥珀酸脱氢酶活性及维持细胞超微结构的完整性,提示这种非创伤性缺氧预处理具有与缺血预处理相类似的抗心肌缺血的作用 相似文献
988.
米非司酮抗着床作用的形态学观察 总被引:5,自引:0,他引:5
采用光镜和透射电镜方法观察米非司酮对大鼠子宫内膜形态结构的影响。实验用30 只成年雌性大鼠分为5 组, 实验组给予米非司酮(C1: 12m g/kg, C2: 6m g/kg, C3: 3m g/kg), 与阴性(A组) 及阳性(B组) 对照组进行比较。结果显示米非司酮用药组子宫内膜和腺体发育受抑制。 相似文献
989.
Narumi Sugihara Takayuki Arakawa Mikae Ohnishi Koji Furuno 《Free radical biology & medicine》1999,27(11-12)
Lipid hydroperoxide (LOOH)–dependent lipid peroxidation was induced in α-linolenic acid (LNA)-loaded hepatocytes by adding Fe, Cu, V, or Cd ions at concentrations from 20 to 500 μM. The effects of structurally related flavonoids at concentrations from 10 to 500 μM on the lipid peroxidation were examined. The results with regard to each flavonoid subclass are as follows: (i) Flavonols such as myricetin, quercetin, fisetin, and kaempferol, but not morin, showed dose-dependent antioxidative activity against metal-induced lipid peroxidation at all metal concentrations. Myricetin, quercetin, and fisetin were the most effective antioxidants, although their efficacies depended on the metal ion. Kaempferol and morin had antioxidative activity equal to the other flavonols in the presence of Cu ions, but were much less effective for the other three metal ions. (ii) Flavones, luteolin, apigenin, and chrysin were antioxidative at low Fe concentrations, but were pro-oxidative at high Fe concentrations. Luteolin exhibited antioxidative activity similar to that of catechol-containing flavonols in the presence of the other three metal ions. Apigenin and chrysin also acted as pro-oxidants with V or with all metal ions, respectively. (iii) Taxifolin, a flavanone, also showed both anti- and prooxidative activity, depending on Fe concentrations, but with other metal showed only antioxidative activity ions. (iv) Epigallocatechin, a flavanol, was antioxidative with all metal ions, and its activity was similar to that of catechol-containing flavonols. The various effects of flavonoids on metal-induced lipid peroxidation in LNA-loaded hepatocytes is discussed with regard to the change in redox potential of flavonoid–metal complexes. 相似文献
990.
Abstract : In this study we have used the presynaptic-rich rat cerebrocortical synaptosomal preparation to investigate the proteolytic cleavage of the amyloid precursor protein (AβPP) by the α-secretase pathway within the βA4 domain to generate a soluble secreted N-terminal fragment (AβPPs ). AβPP was detected in crude cortical synaptosomal membranes, although at a lower density than that observed in whole-tissue homogenates. Protein kinase C (PKC) activation induced a translocation of the conventional PKC isoform β1 and novel PKCε from cytosol to membrane fractions, but there was no alteration in the proportion of AβPP associated with the Tritonsoluble and -insoluble fractions. AβPPs was constitutively secreted from cortical synaptosomes, with this secretion being enhanced significantly by the direct activation of PKC with phorbol ester. The PKC-induced secretion of AβPPs was only partially blocked by the PKC inhibitor GF109203X (2.5 μ M ), whereas the phosphorylation of the myristoylated alanine-rich C kinase substrate (MARCKS) protein was significantly inhibited by GF109203X. The differential sensitivities of the MARCKS phosphorylation and AβPPs secretion to GF109203X may imply that different PKC isoforms are involved in these two events in the synaptosomal system. These findings strongly suggest that the α-secretase activity leading to the secretion of AβPPs can occur at the level of the presynaptic terminal. 相似文献