Suda D, Schwartz J, Shklar G
Eur J Cancer Clin Oncol. 1987 Jan;23(1):43-6. doi: 10.1016/0277-5379(87)90417-2.
Levels of activity for gamma glutamyl transpeptidase (GGT) were studied in hamster buccal pouches developing DMBA-induced epidermoid carcinomas and in pouches in which carcinogenesis was inhibited by topical application of beta carotene. The beta carotene acted to inhibit tumor development when applied topically on days alternate to the application of 0.25% DMBA in heavy mineral oil thrice weekly for 22 weeks. Forty male young adult Syrian hamsters were divided into four equal groups. Group 1 had DMBA applied to left buccal pouches thrice weekly. Group 2 had DMBA applied as in Group 1 but also beta carotene thrice weekly on days alternate to the DMBA application. Group 3 animals were painted with only beta carotene and Group 4 animals were untreated controls. The left buccal pouches were dissected at autopsy and divided in half. One half was fixed in formalin, sectioned in paraffin and stained with hematoxylin-eosin for histologic study. The other half was prepared for the histochemical demonstration of GGT activity using epithelial whole mount preparations. GGT activity was found to be reduced in the left buccal pouches of those animals treated with both beta carotene and DMBA when compared to those animals treated with DMBA alone.
在仓鼠颊囊中研究了γ-谷氨酰转肽酶（GGT）的活性水平，这些颊囊正发展为二甲基苯并蒽（DMBA）诱导的表皮样癌，以及通过局部应用β-胡萝卜素抑制致癌作用的颊囊。当在22周内每周三次在重质矿物油中局部应用0.25% DMBA的日子交替局部应用β-胡萝卜素时，β-胡萝卜素起到了抑制肿瘤发展的作用。将40只雄性成年叙利亚仓鼠分成四个相等的组。第1组每周三次在左颊囊应用DMBA。第2组与第1组一样应用DMBA，但也在与应用DMBA的日子交替时每周三次应用β-胡萝卜素。第3组动物仅用β-胡萝卜素涂抹，第4组动物为未处理的对照。在尸检时解剖左颊囊并将其分成两半。一半固定在福尔马林中，石蜡切片并用苏木精-伊红染色用于组织学研究。另一半制备用于使用上皮整装制剂进行GGT活性的组织化学显示。与仅用DMBA处理的动物相比，发现同时用β-胡萝卜素和DMBA处理的动物的左颊囊中GGT活性降低。
