液氮保存的同种主动脉瓣光镜及电镜观察

目的 研究液氮保存对同种主动脉瓣（ＨＡＶ）组织结构的影响，为临床上合理使用ＨＡＶ提供理论依据。方法 用光镜及电镜对新鲜及液氮保存３个月、８个月、２４个月的ＨＡＶ进行了形态学观察。结果 光镜下各组瓣膜之间的组织结构无明显差异；电镜下，与新鲜ＨＡＶ相比，液氮保存３个月、８个月的ＨＡＶ超微结构改变较轻，保存２４个月的ＨＡＶ可见胶原纤维散乱溶解及断裂，成纤维细胞线粒体肿胀及内质网扩张。结论液氮保存对ＨＡＶ

Light and electron microscopic study on liquid nitrogen preserved homograft aortic valve

Objective To gain insight into the effect of liquid nitrogen(LN) preservation on the tissue structure of homograft aortic valve (HAV) and to provide experimental basis for the application of HAVs.Methods Eight fresh and LN preserved HAVs were divided into four groups:fresh HAVs,LN preserved HAVs with storage periods of 3 months,8 months and 24 months respectively.Each group had two HAVs with six leaflets.All of them were studied with light and electron micoscope.Results The collagen fibers and fibroblast cells appeared well preserved in the specimens with storage periods of 3 months and 8 months compared with the fresh specimens.Divergent,dissolved and ruptured collagenous fibers,swollen mitochondria and dilated endoplasmic reticula in fibroblast cells in the specimens with storage period of 24 months were detectable by electron microscope.No differences could be observed among all the specimens under the light microscope.Conclusion LN has a good structural preservation of HAVs,but it might change their tissue structure.The ultrastructure of HAVs with storage period of 24 months changes markedly.It indicated that the HAVs with LN preserved period of 24 months or longer should not be implanted in the patients.