Linsenmayer T F, Gibney E, Fitch J M
J Cell Biol. 1986 Oct;103(4):1587-93. doi: 10.1083/jcb.103.4.1587.
A unique morphological feature of the embryonic avian cornea is the uniformity of its complement of striated collagen fibrils, each of which has a diameter of 25 nm. We have asked whether this apparent morphological uniformity also reflects an inherent uniformity of the structural and physical properties of these fibrils. For this we have examined the in situ thermal stability of the type I collagen within these fibrils. Corneal tissue sections were reacted at progressively higher temperatures with conformation-dependent monoclonal antibodies directed against the triple-helical domain of the type I collagen molecule. These studies show that the cornea contains layers of collagen fibrils with greater than average stability. The two most prominent of these extend uninterrupted across the entire width of the cornea, and then appear to insert into thick bundles of scleral collagen, which in turn appear to insert into the scleral ossicles, a ring of bony plates which circumscribe the sclera of the avian eye. Once formed, the bands may act to stabilize the shape of the cornea or, conversely, to alter it during accommodation.
胚胎期鸟类角膜的一个独特形态特征是其横纹胶原纤维的组成具有一致性，每条纤维的直径为25纳米。我们探究了这种明显的形态一致性是否也反映了这些纤维在结构和物理特性上的内在一致性。为此，我们检测了这些纤维中I型胶原的原位热稳定性。角膜组织切片在逐渐升高的温度下与针对I型胶原分子三螺旋结构域的构象依赖性单克隆抗体发生反应。这些研究表明，角膜含有稳定性高于平均水平的胶原纤维层。其中最显著的两层连续贯穿角膜的整个宽度，然后似乎插入巩膜胶原的粗束中，而巩膜胶原束又似乎插入巩膜小骨中，巩膜小骨是环绕鸟类眼睛巩膜的一圈骨板。这些带一旦形成，可能起到稳定角膜形状的作用，或者相反，在调节过程中改变角膜形状。
