人、猪、大鼠来源网状层真皮组织学及材料学表征的比较

Comparative analyses of histological and material properties of reticular dermis derived from human, swine and rats

背景:课题组以往研究证实,猪边腹部网状层真皮质地柔软,伸展性也较其他部位好,适合作为异种脱细胞真皮的制作材料,但将其与人网状层真皮和大鼠网状层真皮进行组织形态学和材料学表征的系统对比未见相关报道。目的:研究猪边腹部、大鼠背部与人网状层真皮在组织学、生物力学、分子结构和热稳定性等方面的差异。方法:取人、猪边腹部、Wistar大鼠背部网状层真皮标本并大体观察,石蜡切片后行苏木精-伊红染色、苦味酸-天狼星红染色,显微照相后用图像分析软件测量分析;样本真空干燥并复水后用电子拉伸机测量其力学性能并计算杨氏模量;真空干燥后的样品研碎后用傅里叶红外光谱仪及同步热分析仪分析测量。结果与结论:猪边腹部网状层真皮胶原纤维束直径与人网状层真皮无差异,大鼠背部胶原纤维束较人网状层真皮细(P<0.01);猪边腹部网状层真皮间隙率较人网状层真皮低(P<0.01),大鼠网状层真皮间隙率与人网状层真皮相似(P=0.17)。猪网状层真皮胶原纤维排列紧密杂乱,Ⅰ型胶原蛋白含量及Ⅰ型、Ⅲ胶原蛋白比值高于人网状层真皮(P<0.05),Ⅲ胶原蛋白含量低于人网状层真皮(P<0.05);大鼠网状层真皮Ⅰ型和Ⅲ胶原蛋白含量及其比值与人网状层真皮相近(P>0.05)。3种网状层真皮杨氏模量差异无显著性意义。大鼠网状层真皮胶原蛋白分子有较多的氢键参与,人较少,猪介于两者之间;大鼠网状层真皮热稳定性较好,人和猪次之。

BACKGROUND：Previous studies of our research group have confirmed that the texture of porcine reticular dermis at lateral ventral part is softer and has more extensibility than other parts. Therefore, it may serve as the raw material of xenogenic aceluar dermal matrix. However, its comparison with human and rat reticular dermis has not been reported systematicaly in aspects of histomorphology and material characterization. OBJECTIVE：To compare the reticular dermis from the lateral region of porcine abdomen and rat dorsal part with the reticular dermis from human in histology, biomechanics, molecular structure, thermal stability and other properties. METHODS：The reticular dermis samples were taken from adult human, the lateral region of porcine abdomen, the back of rats, for gross observation. Paraffin sections were observed by hematoxylin and eosin staining and sirius red staining under a light microscopy. The relevant data of micrograph were measured by imagine analysis software. These samples were also vacuum-freezing dried and rehydrated, and then their mechanical properties were tested with a electronic tensile machine to calculate the Young’s modulus. Some vacuum-freezing dried samples were powdered and detected by Fourier transform infrared spectrometer and simultaneous thermal analyzer. RESULTS AND CONCLUSION：There were no differences in colagen fiber bundle diameter of the reticular dermis from adult human and the lateral region of porcine abdomen, but the reticular dermis from the back of rats was thinner than that from adult human （P 〈 0.01）. The gap between the reticular layer of the dermis of the lateral region of porcine abdomen was lower than that from adult human （P 〈 0.0.1）; however, there was no difference in the gap between the reticular layers of the dermis of the rat back and adult human （P=0.17）. Colagen fibers of porcine reticular dermis were arranged tightly in disorder; the content of type I colagen and ratio of type I/III colagen were higher than those in the reticular dermis from adult human （P 〈 0.05）, but the content of type III colagen was less than that in the reticular dermis from adult human （P 〈 0.05）. Contents of type I and III colagen and their ratio were similar between the reticular dermis of rats and adult human （P 〉 0.05）. There was no significant difference in the Young’s modulus of the three kinds of reticular dermises. Hydrogen bonds involved in the reticular dermal colagen molecules ranged as folows： rats 〉 swine 〉 human. Rat reticular dermis has better thermal stability than that of swine and adult human.