用合成受体肽段长期免疫大鼠对其心脏结构和功能的影响(英文)  

Effects of long-term immunization with synthesized receptor peptide on in vivo cardiac activity in rats

作　　者：刘慧荣[1] 

机构地区：[1]山西医科大学生理学教研室,太原030001

出　　处：《山西医科大学学报》2001年第z1期93-99,共7页Journal of Shanxi Medical University

基　　金：卫生部科学研究基金资助!( 9812 94)

摘　　要：用合成的 β1 受体功能表位肽段以及M2 受体功能表位肽段肽连续 18个月免疫大鼠 ,结果发现 :①外周血T淋巴细胞亚群的改变 :T细胞亚群测定结果发现 ,在两免疫组免疫 2 4h后CD4+ /CD8+ 即开始升高 ,到第 7d时达到一个较高的水平 ,3个月时开始下降但仍高于同期对照组 ,第 9个月时降至对照组水平 ,18个月时明显降低 ;对照组的CD4+ /CD8+ 也表现为处理2 4h后升高 ,但从第 3d时开始下降 ,到第 7d时与处理前水平相同 ;②β1 受体肽段和M2 受体肽段免疫大鼠 18个月心功能的改变 :免疫 6、12、18个月后测定心功能显示 ,免疫组dp/dtmax及 -dp/dtmax呈先升高后降低的趋势 ,而对照组则无变化 ;③β1 受体和M2 受体密度与亲和力的改变 ;与对照组相比 ,两免疫组模型受体密度在第 6和第 12个月时呈上调的趋势 ,在 18个月时下调 ;而受体与特异性放射配体的亲和力在 12个月以前变化不明显 ,但在 18个月时则明显降低 ;④心脏体视学指标的改变 ;与对照组相比 ,免疫组大鼠心脏增重 ;β1组左室腔和右室腔明显增大 ,左右室壁变薄 ;M2 组则表现出明显的右室腔变大和右室壁变薄 ,而左室累及较轻 ;⑤心肌组织光学显微镜下的变化 ;两免疫组模型存在有灶状心肌细胞变性、坏死、坏死局部有炎性细胞浸润。⑥心肌细胞电镜变化特点An experiment model of cardiomyopathy was created by immunizing rats for 18 months with synthetic peptides corresponding to the sequence of the second extracellular loop of both β 1 adrenoceptor or M 2 muscarinic receptor. Ninety rats were used and divided into three groups: a control group ( n =30), a group immunized with the peptide corresponding to the (β 1 adrenoceptor (β 1 group, n =30) and a group immunized with the peptide corresponding to the M 2 muscarinic receptor (M 2 group, n =30). To determine if there was a defect of immune regulation in rats of three groups, the percentage of total T cell (CD3 +), helper/induce T cells (CD4 +) and suppressor/cytotoxic T cells (CD8 +) were measured. In the sera from both groups of immunized rats, high titer of anti peptide antibodies were found throughout the study period, but only a low titers of antibodies were found in the sera from some control rats or in the preimmune sera of some immunized rats. The ratio of CD4 +/CD8 + T cells were significantly higher in both immunized groups than that in the control group after 7 days to 3 month of immunization. The myocardial receptor density of both immunized groups displayed a strong trend toward receptor up regulation after 12 months of immunization, but down regulation during 18 month. Both groups of immunized rats displayed significantly enlarged ventricles and thinner walls compared with the control. However, in contrast to the β 1 group, which showed enlarged cavities in both left and right ventricles, the M 2 group was mainly affected in the right ventricles. Moreover, morphological examination of the hearts of rats from immunized groups demonstrated significant alterations such as focal myofibrillar lysis, loss of normal myofilament banding pattern with hypercontraction bands, mitochondrial swelling and condensation, sarcoplasmic vacuolation and deposition of dense granules in both the sarcoplasm and myofibrils. No obvious alterations were noted in the control rats. Eighteen month

关 键 词：心脏受体 肽类 免疫法 心功能 

分 类 号：R331.3+1[医药卫生—人体生理学]