不同复温方法对深低温冷冻复合组织血管活性的影响

目的比较3种不同复温方法对深低温冷冻的复合组织中血管活性的影响,找出一种对复合组织中血管损伤最小的复温方法。方法选用20只新西兰大白兔随机分成四组,切取双侧后肢(对照组为新鲜断肢取血管),三个实验组标本经梯度降温后放入液氮中保存7天。分别采用37℃水浴复温组(A组)、空气复温组(B组)、-20℃冰复温组(C组)方法进行复温。采用光镜、免疫组化方法观察血管内皮细胞活性,结果进行统计学分析。结果光镜观察,A组、B组内皮细胞大片脱落,平滑肌细胞变形;而C组内皮细胞和平滑肌细胞保存较好,更接近对照组;免疫组化检测中,3种复温方法血管内皮中均可见VEGF及CD34呈斑片状的弱表达,-20℃冰复温组(C组)VEGF及CD34的表达更接近对照组,高于37℃水浴复温组(A组)及空气复温组(B组)(P<0.05)。结论 3种不同复温方法对深低温冷冻的复合组织中血管活性影响不同,-20℃冰复温法影响最小。

Biological activity study of cryopreserved composite tissue with different thawing methods

【Objective】To observe the effects of three different thawing methods on the vascular activity of cryopreserved composite tissue so as to find a better thawing method to the cryopreserved composite tissue.【Methods】20 New Zealand white rabbits were selected in our test,they were randomly divided into four groups.The rabbits hind legs are cut as the specimens(but the control group without any treatment).Three experimental groups are stored in the liquid nitrogen for 7 days after after gradient freezing.The test specimens are thawed by three different methods(at 37℃ for thawing(group A),air thawing(group B),-20℃ ice thawing(Group C)).The histological changes are observed by light microscopy and immunohistochemical methods,and the result are analysised the statistical methods.【Results】The result of optical microscope: There is a large loss in endothelial cells and deformation in smooth muscle cells in Group A and B.And Group C is close to the control group,which is well preserved to the endothelial cells and smooth muscle cells.The result of Immunohistochemistry: There was patchy weak expression in vascular endothelial after 3 different kind thawing methods.Among the 3 groups,-20℃ ice thawing(Group C) is closer to the control group in VEGF and CD34 expression,and it is higher than the other 2 thawing methods(at 37℃ for thawing(group A),air thawing(group B)(p<0.05).【Conclusion】There are different effect on the vascular activity of the cryopreserved composite tissue after 3 different thawing methods,and-20 ℃ ice thawing produce the minimal impact.