急性切口痛对大鼠脊髓背角缝隙连接蛋白Cx43表达的影响

目的观察急性切口痛对大鼠脊髓背角缝隙连接蛋白Connexin43（Cx43）表达的影响。方法雄性SD大鼠80只,随机分为
对照组和急性切口痛模型组,切口痛模型组所有大鼠于左后爪作一纵形切口制备切口痛模型,于术前和术后1、2、4、6、24 h时采
用von frey 细丝法测定大鼠左后足机械回缩阈值的改变。于术前和术后2 h、4 h取大鼠左侧脊髓背角组织,分别采用Western
blot 法和免疫荧光标记法检测脊髓背角Cx43蛋白表达的变化。结果急性切口痛组大鼠50%机械性回缩阈值在术后24 h内显
著降低,并于2 h, 4 h 最为显著,与对照组比较差异均有统计学意义（P<0.01）;Western blot 结果显示,急性切口痛组脊髓背角
Cx43的表达于术后2 h和4 h明显升高,与对照组比较差异有统计学意义（P<0.01）;免疫荧光结果显示,急性切口痛组脊髓背角
Cx43的免疫荧光强度于术后2、4、24 h明显升高,与对照组比较差异有统计学意义（P<0.01）。结论急性切口痛能够引起脊髓
背角缝隙连接蛋白Cx43的表达明显升高,缝隙连接蛋白Cx43可能参与急性切口痛的产生。
     

正常成人窦房结形态学及Cx43、Cx40的表达

目的 观察正常成人心脏窦房结的细胞构筑及连接蛋白43、40(connexin43、40,Cx43、Cx40)的表达和分布情况. 方法 常规石蜡包埋,HE、Masson染色,选定目标部位行Cx43、Cx40免疫组织化学染色,并进行图像及统计分析. 结果 ①正常成人窦房结细胞组成、形态、排布区别于普通工作心肌.②由房肌、窦房结外周到动脉周围结组织,Cx43、Cx40表达逐渐减弱,胞质染色逐渐浅淡;而Cx40的分布范围在动脉周围窦房结组织中多于外周结组织. 结论 正常成人窦房结的细胞组成、排布及Cx43、Cx40的表达与其电生理起搏、传导特性相符.     

Connexins in neurons and glia：targets for intervention in disease and injury

Both neurons and glia throughout the central nervous system are organized into networks by gap junctions. Among glia, gap junctions facilitate metabolic homeostasis and intercellular communication. Amo...     

Impaired compensatory beta‐cell function and growth in response to high‐fat diet in LDL receptor knockout mice

In this study, we investigated the effect of low density lipoprotein receptor (LDLr) deficiency on gap junctional connexin 36 (Cx36) islet content and on the functional and growth response of pancreatic beta-cells in C57BL/6 mice fed a high-fat (HF) diet. After 60 days on regular or HF diet, the metabolic state and morphometric islet parameters of wild-type (WT) and LDLr−/− mice were assessed. HF diet-fed WT animals became obese and hypercholesterolaemic as well as hyperglycaemic, hyperinsulinaemic, glucose intolerant and insulin resistant, characterizing them as prediabetic. Also they showed a significant decrease in beta-cell secretory response to glucose. Overall, LDLr−/− mice displayed greater susceptibility to HF diet as judged by their marked cholesterolaemia, intolerance to glucose and pronounced decrease in glucose-stimulated insulin secretion. HF diet induced similarly in WT and LDLr−/− mice, a significant decrease in Cx36 beta-cell content as revealed by immunoblotting. Prediabetic WT mice displayed marked increase in beta-cell mass mainly due to beta-cell hypertrophy/replication. Nevertheless, HF diet-fed LDLr−/− mice showed no significant changes in beta-cell mass, but lower islet–duct association (neogenesis) and higher beta-cell apoptosis index were seen as compared to controls. The higher metabolic susceptibility to HF diet of LDLr−/− mice may be explained by a deficiency in insulin secretory response to glucose associated with lack of compensatory beta-cell expansion.     

缝隙连接在血管内皮和平滑肌细胞中的作用及其与高血压的关系

细胞间的直接通讯--缝隙连接在控制和协调血管功能方面起重要作用。缝隙连接是沟通相邻细胞质膜的唯一一类通道,为离子、小分子代谢物质、第二信使等细胞间信号分子的直接交换提供一个通道。血管内皮细胞和平滑肌细胞表达多种类型缝隙连接蛋白(connexin,Cx),多种Cx 在心血管系统中的共同表达并协调一致地工作,对心血管系统的发育、平滑肌和内皮细胞功能的整合、以及对血管壁细胞功能协调等起着重要作用。在血管发生疾病时Cx表达相应发生改变,以与缝隙连接调节血管紧张度和动脉血压的作用相一致。本综述讨论了在血管内皮和平滑肌细胞在生理和病理情况下(以高血压为例)缝隙连接对血管结构和功能的影响。     

兔心房及肺静脉肌袖组织结构和Cx40、Cx43表达的增龄性改变

目的通过研究家兔心房和肺静脉肌袖(PVs)的组织结构及缝隙连接蛋白(cx)的增龄性改变,探讨增龄与房颤的关系,为增龄是否是房颤发生的主要或独立危险因素提供实验依据。方法以家兔为研究对象,测量各组家兔心电图的P波时限,分离不同年龄组家兔心房、肺静脉肌袖组织,用组织化学和免疫组化的方法检测胶原纤维和缝隙连接蛋白的表达。结果 P波的Pa、Pmax、Pmin和Pd随着增龄均显著延长,差异有统计学意义(PO.05);心肌间质中胶原纤维容积分数随着增龄逐渐增多.差异有统计学意义(P0.05);心房和肺静脉肌袖组织随着增龄Cx43的表达量呈明显的下降趋势,差异有统计学意义(P0.05)。结论P波时限、胶原纤维含量和缝隙连接蛋白均存在增龄性改变。     

De novo balanced translocation (6;18)(q21;q21.3) in a patient with heterotaxia

We report on a sporadic case of heterotaxia with a de novo chromosome structural abnormality. The patient had inversely located heart (dextrocardia), stomach, duodenum, and cecum. In addition, she had cerebral atrophy, hypertelorism with telecanthus, infraorbital skin furrows, ear-lobe grooves, prominent maxilla and teeth, large carp mouth, short fifth fingers with limited flexion, generalized hypotonicity, and severe psychomotor retardation. High-resolution chromosome banding analysis demonstrated an apparently balanced translocation: 46,XX,t(6;18)(q21;q21.3). It is hypothesized that both heterotaxia and the chromosomal abnormality in the patient are causally related and a putative situs determining gene has been disrupted by the chromosome break, i.e., a position effect or a cryptic deletion at around the breakpoints. The translocation in our patient may be a good source for positional cloning of the gene. © 1996 Wiley-Liss, Inc.