Holbrook K A, Byers P H, Counts D F, Hegreberg G A
J Invest Dermatol. 1980 Feb;74(2):100-4. doi: 10.1111/1523-1747.ep12520000.
Dermatosparaxis is a connective tissue disease, primarily of sheep and cattle, that results from deficient activity of the NH2-terminal procollagen peptidase. It is characterized by fragile, loose skin that is easily torn with minor trauma. We have identified a cat twith a defect in this procollagen peptidase which affects only a small proportion of the collagen molecules; the majority of the collagen is processed normally. Nonetheless, as seen by transmission and scanning electron microscopy, this population of aberrant collagen molecules significantly alters the structure of individual collagen fibrils, the assembly of fibrils into fiber bundles and the integration of fiber bundles into a normal, woven network in the reticular dermis of skin. Although the clinical findings are less severe than those in sheep and cattle where the enzymatic defect is more complete, the ultrastructural abnormalities are marked and demonstrate that a minority of abnormal collagen molecules cn have a major effect on the structure and function of connective tissues.
皮肤松垂症是一种主要发生于绵羊和牛的结缔组织疾病，由氨基端前胶原肽酶活性不足引起。其特征是皮肤脆弱、松弛，轻微创伤即可导致皮肤撕裂。我们发现一只猫存在这种前胶原肽酶缺陷，该缺陷仅影响一小部分胶原分子；大多数胶原正常加工。尽管如此，通过透射电子显微镜和扫描电子显微镜观察发现，这群异常胶原分子显著改变了单个胶原纤维的结构、纤维组装成纤维束的过程以及纤维束整合到皮肤网状真皮中正常编织网络的过程。虽然该猫的临床症状不如酶缺陷更完全的绵羊和牛严重，但超微结构异常明显，表明少数异常胶原分子可对结缔组织的结构和功能产生重大影响。
