Chen C J, Kang J, Shieh T Y
Department of Oral and Maxillo-Facial Surgery, School of Dentistry, Kaohsiung Medical College, Taiwan, Republic of China.
Kaohsiung J Med Sci. 1997 Jul;13(7):432-9.
The typical wound healing process after tooth extraction includes several important biological reactions. The collagen fiber, which is the main organic component of connective tissue, plays an important role in the formation of granulation tissue and also bone tissue. Maturation of collagen is controlled by the intermolecular crosslinks in the collagen fibers. Lysyl oxidase, which catalyzes the corresponding aldehyde formation from certain lysyl and hydroxylysyl residues in collagen and elastin in the first step of the linking reaction, is the only known enzyme required in the crosslinking process. This study was designed to analyze changes in the lysyl oxidase activity and calcium content during the healing of rabbit tooth extraction wounds and to survey the relationship between them. Healing tissue in the extraction sockets was removed 1, 2, 3, 4, 5, 7, 10, 14, 21, 28, and 56 days postoperatively. After decalcification, lysyl oxidase was extracted from wound tissue, and activity of this enzyme was examined by tritium-release assay. Radiographs and histologic sections were also obtained in each group. The results show that lysyl oxidase activity can be detected on the first day postoperatively and that it increases sharply from days five to seven, reaching the peak value on the seventh day. After that, enzyme activity decreases gradually and returns to normal range on day 14. Histologically, the healing sockets were filled mainly with young fibrous connective tissue at day seven; osteoid tissue could be found on the lateral wall and fundus of the extraction sockets at the same time. Accompanying the formation of new bone, calcium content increased conspicuously from day 7 to day 14. These results indicate that lysyl oxidase predominantly acts to promote cross-linking of the abundantly synthesized collagen in the early stage of healing of rabbit tooth extraction wounds. When minerals were precipitated at a great rate in the newly-formed bone, lysyl oxidase activity was concurrently decreased.
拔牙后的典型伤口愈合过程包括几个重要的生物学反应。胶原蛋白纤维是结缔组织的主要有机成分，在肉芽组织以及骨组织的形成中发挥重要作用。胶原蛋白的成熟受胶原纤维中分子间交联的控制。赖氨酰氧化酶在交联反应的第一步催化胶原蛋白和弹性蛋白中某些赖氨酰和羟赖氨酰残基形成相应的醛，是交联过程中唯一已知所需的酶。本研究旨在分析兔拔牙伤口愈合过程中赖氨酰氧化酶活性和钙含量的变化，并探究它们之间的关系。术后1、2、3、4、5、7、10、14、21、28和56天取拔牙窝内的愈合组织。脱钙后，从伤口组织中提取赖氨酰氧化酶，并用氚释放法检测该酶的活性。每组还获取了X线片和组织学切片。结果显示，术后第一天即可检测到赖氨酰氧化酶活性，从第5天到第7天急剧增加，在第7天达到峰值。之后，酶活性逐渐下降，在第14天恢复到正常范围。组织学上，第7天时愈合的拔牙窝主要充满年轻的纤维结缔组织；同时在拔牙窝的侧壁和底部可发现类骨质组织。随着新骨的形成，钙含量从第7天到第14天显著增加。这些结果表明，赖氨酰氧化酶在兔拔牙伤口愈合早期主要作用是促进大量合成的胶原蛋白的交联。当矿物质在新形成的骨中大量沉淀时，赖氨酰氧化酶活性同时降低。
