O'Sullivan M, Tipton K F, McDevitt W E
Department of Restorative Dentistry and Periodontology, School of Dental Science, Trinity College, Dublin 2, Ireland.
Arch Oral Biol. 2002 May;47(5):399-406. doi: 10.1016/s0003-9969(02)00009-2.
The semicarbazide-sensitive amine oxidase (EC 1.4.3.6; SSAO) from crude homogenates of human dental pulp was shown to catalyse the oxidative deamination of 5-hydroxytryptamine (serotonin; 5-HT) with a K(m) of 318+/-52 microM. In this respect the human enzyme resembles that in pig dental pulp, but differs from SSAO in all other tissues studied, which are inactive towards 5-HT. A method is described for obtaining intact dental pulp in which the anatomical details are preserved. Extracted teeth are frozen in dry ice and later defrosted rapidly before being fractured in a mechanical vice, facilitating pulp removal. Immunohistochemistry showed SSAO in the odontoblast layer, nerve fibres and blood vessels. The presence of SSAO in nerves in dental pulp appears to be unique. Tryptophan hydroxylase, a key enzyme in 5-HT synthesis, was also demonstrated in nerves and the odontoblast layer of human dental pulp.
人牙髓粗匀浆中的氨基脲敏感胺氧化酶（EC 1.4.3.6；SSAO）可催化5-羟色胺（血清素；5-HT）的氧化脱氨反应，其米氏常数（K(m)）为318±52微摩尔。在这方面，人源酶类似于猪牙髓中的酶，但与其他所有研究组织中的SSAO不同，其他组织中的SSAO对5-HT无活性。本文描述了一种获取完整牙髓的方法，该方法可保留牙髓的解剖细节。将拔除的牙齿在干冰中冷冻，之后在机械虎钳中折断前迅速解冻，以便于取出牙髓。免疫组织化学显示，成牙本质细胞层、神经纤维和血管中存在SSAO。牙髓神经中存在SSAO似乎是独一无二的。色氨酸羟化酶是5-HT合成中的关键酶，在人牙髓的神经和成牙本质细胞层中也有表达。
