A, the comparation expression of type I collagen mRNA in KM; B, type III collagen mRNA expression in KM; C, type I collagen mRNA expression in FM; D, type III collagen mRNA expression in FM; E, production of type I collagen; F, production of type III collagen: a to d shows significant difference of protein expression of KM (*P<0.05), and e and f shows significant difference of protein expression of FM (*P<0.05). n=3.