中、长期模拟失重大鼠心肌间质Ⅰ、Ⅲ型胶原的变化

Changes of typeⅠand type Ⅲ collagens in rat myocardium after medium and long term simulated weightlessness

目的 研究中期及长期模拟失重对大鼠心肌 、 型胶原的影响。 方法 以尾部悬吊大鼠模型模拟失重对机体的影响。用免疫组织化学方法及计算机显微图像分析法观察了尾部悬吊 4周(suspended 4- week,SUS- 4)、尾部悬吊 13周 (suspended 13- week,SU S- 13)大鼠与同步对照大鼠(controls,CON- 4,CON- 13)左室各部位心肌、室间隔与右室心肌 、 型胶原的改变。 结果 与CON- 4相比 ,CON- 13各部位胶原总量及 、 型胶原均呈增加趋势 ,右室心肌 型胶原及左室心肌内膜下区 型胶原的差别有显著性的意义 ,分别增加 112 .2 % (P<0 .0 1)、18.7% (P<0 .0 5 )。与 CON- 4相比 ,SUS- 4各部位心肌 、 型胶原有增加趋势 ,但差别没有显著性的意义。与 CON- 13相比 ,SUS- 13左室心肌胶原总量显著增加 ;左室心内膜下区、心肌膜及全部左室心肌 型胶原分别增加6 9.1%、6 2 .1%及 5 1.6 % (P<0 .0 5 ) ;左室心内膜下区及全部左室心肌 型胶原分别增加 6 1%及39.7% (P<0 .0 5 )。与 SU S- 4相比 ,SUS- 13左室心内膜下区、心肌膜、整个左室心肌及右室心肌 型胶原显著增加 (P<0 .0 5 ) ;左室各部位心肌 型胶原显著增加 (P<0 .0 5 )。 结论 中、长期模拟失重均可对大鼠心肌胶原间质产生影响 ,长期模拟失重可导致大鼠左?

Objective The purpose of the present study was to investigate changes of typeⅠand type Ⅲ collagen in rat myocardium after medium and longterm simulated weightlessness. Methods The -30° head down tail suspension rat model was used to simulate weightlessness. TypeⅠ and type Ⅲ collagen in the lateral walls of the left ventricle, right ventricle and septum of 4 wk and 13 wk tail suspended rats (SUS 4, SUS 13) as well as their respective synchronous controls (CON 4, CON 13) were examined by immunohistochemistry and automatic image analysis. Results Compared with CON 4, in CON 13 rats, the content of collagen and typeⅠand type Ⅲ collagen showed a trend of increase and the contents of typeⅠcollagen in the right ventricular myocardium and type Ⅲ collagen in left ventricular subendocardium showed significant increases by 112.3 % ( P < 0.01 ) and 18.7%( P <0.05), respectively. Compared with CON 4, the contents of total collagen, typeⅠand type Ⅲ collagen in various parts of the myocardium showed a trend of increase in the SUS 4 , but did not reach statistical significance. Compared with CON 13, the total content of collagen in left ventricular myocardium of SUS 13 was increased; typeⅠcollagen in left ventricular subendocardium, midwall and left ventricular myocardium were increased by 69.1%, 62.1%, and 51.6% ( P <0.05 ) respectively, and the type Ⅲ collagen in left ventricular subendocardium and left ventricular myocardium was increased by 61% and 39.7%( P <0.05) respectively. In SUS 13, contents of typeⅠcollagen in left ventricular subendocardium, midwall, left ventricular myocardium, and right ventricular myocardium and type Ⅲ collagen in all parts of left ventricular myocardium were also significantly increased ( P <0.05), as compared with those of SUS 4. Conclusions Long term simulated weightlessness might aggravate collagen deposition in rat myocardium.