Differential effect of oestrogen on post‐exercise cardiac muscle myeloperoxidase and calpain activities in female rats

The effects of oestrogen administration on 1 h post‐exercise cardiac muscle myeloperoxidase (MPO) and calpain activities were determined in female rats. Rats were ovariectomized and implanted for 2 weeks with either oestrogen (25 mg 17‐oestradiol) or placebo pellets or left with ovaries intact. Rats were then run for 1 h at 21 m min^–1, 12% grade, killed 1 h post‐exercise and cardiac muscle and blood samples were removed. Control animals from each group were killed without prior exercise. Serum oestrogen levels in the order of the highest to lowest were; ovariectomized oestrogen replaced rats > intact ovaries rats > ovariectomized placebo rats. Oestrogen induced significant (P < 0.05) elevations in cardiac MPO activity at rest and at 1 h post‐exercise in ovariectomized rats. No significant elevations in cardiac MPO activity were evident in placebo ovariectomized or normal ovary rats at rest or post‐exercise. Cardiac calpain activities were similar in all unexercised groups. Ovariectomized placebo and intact ovary rats had significantly (P < 0.05) elevated cardiac calpain activities 1 h post‐exercise while calpain activity was not significantly elevated in hearts from ovariectomized oestrogen rats. These results demonstrate that oestrogen supplementation in ovariectomized rats induces elevations in cardiac muscle MPO activities at rest and at 1 h post‐exercise. This is opposite to the effect of oestrogen in post‐exercise skeletal muscle and implies a greater neutrophil infiltration into cardiac muscle caused by oestrogen. This effect cannot be explained by changes in 1 h post‐exercise cardiac muscle calpain activity, the elevation of which was suppressed by oestrogen administration. Oestrogen influences cardiac calpain activity similarly to its effect in skeletal muscle. Thus, oestrogen administration to ovariectomized rats induces elevations in cardiac MPO activity while suppressing cardiac calpain activity.     

二硫化碳对大鼠胚胎发育及血清锌和铜含量影响的研究

本文观察了CS_2对大鼠胚胎发育及血清锌、铜含量的影响。发现胚胎着床前死亡率升高,胎鼠皮下出血、心包淤血及骨骼骨化不金的发生率增高。但无明显的致畸效应。14.1及103.9ng/m~3的CS_2对妊娠大鼠的血清锌、铜含量无明显影响。说明CS_2对大鼠的胚胎毒性与其对妊娠大鼠血清锌、铜含量的影响之间没有关联。     

大鼠氮能神经与胃电节律失常的关系

目的 :探讨一氧化氮与胃电节律失常的关系 .方法 :2 8只大鼠随机分为 3组 :正常对照组 (12只 )和胃电节律失常模型组 (8只 )喂养 4wk后 ,先记录胃电、再行胃窦肌间神经丛氮能神经染色 ;药物组 (8只 ) :观察注射不同剂量硝普钠 (SNP)、一氧化氮合酶抑制剂左型精氨酸甲酯 (L NAME)后的胃电变化 .结果 :药物组大鼠注射硝普钠或大剂量L NAME后出现了明显的胃电节律失常 ;模型组大鼠胃电节律失常增加 ,异常节律指数 (ARI)和慢波频率变异系数 (coefficientofvariation,CV)分别为 2 1.8%和 2 5 .7% ,明显高于正常对照组大鼠 (ARI和CV分别为 9.5 %和 17.2 % ,P <0 .0 1) ,胃窦肌间神经丛的氮能神经含量也明显多于正常对照组 (2 1.9%vs13.8% ,P <0 .0 1) .结论 :一氧化氮增多或过少均可导致明显的胃电节律失常     

穹隆-海马伞切断对大鼠脑内TrkA表达的影响

①目的　探讨穹隆 海马伞切断对大鼠脑内不同部位神经生长因子受体TrkA表达的影响及临床意义。②方法　成年健康雌性Wistar大鼠 10只 ,随机分为穹隆 海马伞切断模型组和假手术组。两组大鼠均常规取海马CA1区、皮质区、杏仁复合体区、基底前脑Meynert核等部位脑组织与假手术组比较TrkA阳性细胞表达情况。③结果　假手术组大脑各观察区有基础水平的TrkA表达。模型组大脑海马CA1区、大脑皮质区、杏仁复合体区以及Meynert核区TrkA阳性细胞数明显减少 (t=3.94 4～ 8.4 4 2 ,P <0 .0 5 )。 ④结论　穹隆 海马伞切断可致大鼠脑内多部位TrkA表达减少 ,其可能是导致认知和情绪损伤的原因之一。     

女性生殖道不同部位检测支原体的序贯试验分析

目的探讨解脲脲原体和人型支原体在女性生殖道的主要寄生部位.方法采用载量一致的标准无菌棉拭子分别于女性阴道穹窿和宫颈口采样,用法国生物梅里埃ID试剂进行解脲脲原体和人型支原体的培养鉴定及半定量计数,按照双向质反应开放型序贯试验设计,对检测结果进行比较分析.结果阴道穹窿部位标本中两种支原体的总阳性数和≥10^4ccu/ml半定量阳性数均高于宫颈口标本.结论对女性进行生殖道支原体感染的检测时应采集阴道穹窿标本,以提高检出率.     

The effect of the fiber components cellulose and lignin on experimental colon neoplasia

Sixty Sprague-Dawley rats were pair-fed one of three nutritionally identical diets. One diet contained “low-fiber” (3.8% crude fiber); the others contained “high fiber” (28.7% crude fiber) composed of either cellulose or lignin. Although both “high fiber” diets had similar stool bulking effects, only the cellulose diet was associated with a reduction in 1,2-dimethylhydrazine (DMH)-induced colon neoplasms. The cellulose diet was also associated with distinct changes in the gut bacterial profile and with a lowered serum cholesterol. © 1993 Wiley-Liss, Inc.     

Roles of DNA polymerase β on repair of DNA damaged by γ－rays irradiation

ＲｏｌｅｓｏｆＤＮＡｐｏｌｙｍｅｒａｓｅβｏｎｒｅｐａｉｒｏｆＤＮＡｄａｍａｇｅｄｂｙγ－ｒａｙｓｉｒｒａｄｉａｔｉｏｎＣａｉＪｉａｎｍｉｎｇ（蔡建明）；ＺｈｅｎｇＸｉｕｌｏｎｇ（郑秀龙）；ＬｕｏＣｈｅｎｇｊｉ（罗成基）；ＧａｏＪｉａｎｇｕｏ（高建国...     

大鼠正中隆起及垂体结节区生长抑素免疫阳性成分的分布

应用免疫组织化学方法观察了大鼠正中隆起及垂体结节区内生长抑素免疫阳性成分的分布,新发现:在交叉后区的正中隆起前部内侧带,有少量的生长抑素免疫阳性神经元胞体;少量阳性纤维几乎垂直行向腹侧,有的可达脑膜表面。垂体结节区内可见较密集的生长抑素阳性纤维丛,其上可见较多的膨体;一些纤维同样到达腹侧表面。     

热休克反应对大鼠油酸肺保护作用的机制研究

未研究发现，经热休克处理的大鼠注油酸后，肺组织损伤明显减轻，Ｗｅｓｔｅｒｎ印迹分析显示热休克使大鼠肺组织中ＨＳＰ７０含量明显增多；Ｎｏｒｔｈｅｒｎ印迹分析证实此乃由于ＨＳＰ７０ｍＲＮＡ转录增加所致。说明热休克处理使肺组织ＨＳＰ７０基因表达增强；提示热休克反应对大鼠油酸肺的保护作用与肺组织细胞中ＨＳＰ７０基因表达增强及与ＨＳＰ７０增多有关。