Hayasaka S, Nakazawa M, Ishiguro S, Mizuno K
Graefes Arch Clin Exp Ophthalmol. 1986;224(3):310-2. doi: 10.1007/BF02143076.
We examined tyrosinase activity in pigmented specimens from three cases of ocular malignant melanoma. Tissue (cholate-trypsin-treated) extract was prepared in cholate-phosphate buffer by homogenization, centrifugation, trypsin digestion, and hydroxylapatite column chromatography. Tyrosinase activity was spectrophotometrically assayed as dopa (L-3,4-dihydroxylphenylalanine) oxidase activity. Tyrosinase activity was detected in the cholate-trypsin-treated extracts. Enzyme activity was inhibited by phenylthiourea but not by 3-iodo-tyrosine. The enzyme was inactivated when extract was preheated or digested with pronase. We believe that our findings confirm the presence of tyrosinase activity in ocular malignant melanoma.
我们检测了3例眼部恶性黑色素瘤色素沉着标本中的酪氨酸酶活性。通过匀浆、离心、胰蛋白酶消化和羟基磷灰石柱色谱法，在胆酸盐 - 磷酸盐缓冲液中制备组织（经胆酸盐 - 胰蛋白酶处理）提取物。酪氨酸酶活性通过分光光度法测定为多巴（L - 3,4 - 二羟基苯丙氨酸）氧化酶活性。在经胆酸盐 - 胰蛋白酶处理的提取物中检测到酪氨酸酶活性。酶活性被苯硫脲抑制，但不被3 - 碘酪氨酸抑制。当提取物预热或用链霉蛋白酶消化时，酶失活。我们认为我们的研究结果证实了眼部恶性黑色素瘤中存在酪氨酸酶活性。
