组织原卟啉IX与大鼠大肠癌在体自体荧光差异的相关性研究

Relation between tissue protoporphyrin IX and rat colorectal carcinoma laser induced autofluorescence in vivo

目的 探讨组织原卟啉IX含量与大鼠大肠癌在体自体荧光差异的相关性。方法 60只SD大鼠以 1,2 二甲肼 (DMH ) 2 5mg/kg体重注射腹腔 ,1周 1次 ,持续 18周 ,成功诱导大鼠大肠癌。 2 0周后以 3 70nm激光诱导自体荧光检测分析系统采集实验组大鼠癌组织和正常组织40 0～ 70 0nm范围内的在体自体荧光 ;采用荧光分光光度计检测癌组织原卟啉IX、正常组织原卟啉IX。结果 各组组织在体自体荧光光谱 460nm左右处大多有荧光峰 ;73 %的进展期癌组织、69%的早期癌组织在 63 5nm附近有荧光峰。早期癌组和进展期癌组I63 5/I460 值较正常组大 ,差异有显著性 (P <0 .0 5 ) ,早期癌组和进展期癌组I63 5/I460 值差异无显著性 (P >0 .0 5 ) ;正常组织原卟啉IX、早期癌组的组织原卟啉IX、进展期癌组织原卟啉IX含量分别为 (3 17.0 99± 16.85 9)ng/g组织、(4 16.814± 6.786)ng/g组织和(60 6.874± 2 1.798)ng/g组织 ,早期癌组和进展期癌组织原卟啉IX较正常组织原卟啉IX大 ,差异有非常显著性 (P <0 .0 0 1) ,进展期癌组织原卟啉IX较早期癌组织原卟啉IX大 ,差异有非常显著性 (P <0 .0 0 1)。结论 大鼠正常大肠组织在体自体荧光和大鼠大肠癌在体自体荧光 63 5nm存在差异。 63 5nm处的差异可能是组织原卟啉IX内源性积聚引起的?

Objective To investigate the mechanism of laser induced autofluorescence in vivo of rat colorectal carcinoma by studying tissue protoporphyrin IX.Methods DMH (25 mg per kg) was injected into 60 Sprague-Dawley rat abdominal cavity once a week for 18 weeks.At 20th week,laser induced autofluorescence in vivo excited at 370 nm was collected in experimental group.Results Different stage tissues showed peaks at 460 nm.73% of advanced colorectal carcinoma and 69% of early stage colorectal carcinoma showed a peak at 635 nm.I 635/I 460 in early stage colorectal carcinoma and advanced colorectal carcinoma was higher than that in normal tissue (P< 0.05).There was no significant difference between I 635/I 460 in early stage colorectal carcinoma and that of advanced colorectal carcinoma (P> 0.05).Protoporphyrin IX in normal tissue,early stage colorectal carcinoma and advanced colorectal carcinoma was (317.099± 16.859) ng/g, (416.814± 6.786) ng/g and (606.874± 21.798) ng/g respectively.The protoporphyrin IX in advanced colorectal carcinoma was higher than that in normal tissue,early stage colorectal carcinoma (P< 0.001).The protoporphyrin IX in early stage colorectal carcinoma was higher than that in normal tissue (P< 0.001).Conclusion Laser induced autofluorescence in normal rat colorectal tissue and rat different-stage colorectal carcinoma in vivo at 635 nm is different.Difference in laser induced autofluorescence in vivo at 635 nm may be caused by tissue protoporphyrin IX and blood protoporphyrin IX.