Effect of Carcinogenic Heterocyclic Amine, EGF, and FGF on the Tooth-germ

1 .本研究采用组织学、AgNOR银染色、PCNA免疫组化染色等方法研究了Trp-P-2的应用对大鼠口腔黏膜的影响。A组（对照组）牙龈、颊黏膜组织结构正常，AgNOR计数和PCNA百分比正常。B组（DMSO组）龈、颊粘膜的组织学、AgNOR计数及PCNA百分比与a组相似。C组（Trp-P-2组）龈、颊粘膜上皮组织增生轻度改变，为a组所未见，基底细胞排列不规则，细胞异型化，棘细胞排列不规则，增生；角化细胞层增厚，上皮突起不规则伸长。这些变化在牙龈和颊粘膜之间几乎相似。与a组比较，龈、颊粘膜AgNOR计数和PCNA百分比均有统计学意义（P<0.01）。本研究结果表明，应用Trp-P-2可引起动物龈、颊粘膜上皮异常增生的改变。2 .本研究的目的是通过组织学和BrdU方法探讨表皮生长因子（EGF）和胰岛素样生长因子（IGF-I）对口腔粘膜的影响小鼠牙胚在器官培养中的发育。采用组织学和BrdU法检测A组（BGJb）、B组（EGF 100ng/ml）、C组（EGF 200ng/ml）、D组（IGF 50ng/ml）、E组（IGF 100ng/ml）、F组（EGF 100ng/ml和IGF 50ng/ml）、G组（EGF 100ng/ml和IGF 100ng/ml）、H组（EGF 200ng/ml和IGF 50ng/ml）、I组（EGF 200ng/ml和IGF 100ng/ml）牙胚。B组、C组牙胚上皮细胞增殖与A组比较有明显差异，D组、E组牙胚上皮细胞增殖与A组比较无明显差异。F、G、H、I组牙胚上皮细胞增殖与A组比较有明显差异。本研究结果表明，在器官培养中，EGF促进了小鼠牙胚上皮细胞的增殖，但也提示IGF-I对小鼠牙胚上皮细胞的增殖没有刺激作用。少

I.In this study, the effects of applications of Trp-P-2 on the oral mucosa of the rat were investigated by histology and AgNOR silver staining and PCNA immunohistochemical staining methods. In Group A (control group), Gingiva and buccal mucosa showed a normal histological structure and also normal AgNOR counts and PCNA percentages. In Group B (DMSO group), Gingiva and buccal mucosa were similar in histology, AgNOR counts and PCNA percentages to those of Group A.In Group C (Trp-P-2 group), Gingiva and buccal mucosa displayed mild changes of epithelial displasia, which were not seen in those of Group A.These epithelial changes were irregular arrangement and cellular atypia of basal cells, irregular arrangement and proliferation of prickle cells, thickening of the keratinized cell layer and irregular elongation of epithelial projections. These changes were almost similar between gingiva and buccal mucosa. The AgNOR counts and PCNA percentages in gingiva and buccal mucosa were statisticall … More y significant (P<0.01) compared with those of Group A.The results of the present study suggested that application of Trp-P-2 produced the changes of epithelial dysplasia in gingiva and buccal mucosa of the animal.II.The purpose of the present study was to investigate by histology and BrdU method the effects of EGF (epidermal growth factor) and IGF-I (insulin-like growth factor-I) on the development of the mouse tooth-germ in organ culture. The tooth germs of Groups A (BGJb), B (EGF 100ng/ml), C (EGF 200ng/ml), D (IGF 50ng/ml), E (IGF 100ng/ml), F ( EGF 100ng/ml and IGF 50ng/ml) , G (EGF 100ng/ml and IGF 100ng/ml) , H (EGF 200ng/ml andIGF 50ng/ml ) and I ( EGF 200ng/ml and IGF 100ng/ml) were examined by histology and BrdU method. The epithelial cell proliferation of the tooth germs in Groups B and C were marked as compared with that in Group A.However, the epithelial cell proliferation of the tooth germs in Groups D and E were similar to that in Group A.Though the epithelial cell proliferation of the tooth germs in Groups F, G, H and I were marked as compared with that in Group A, it was similar to those in Groups B and C.The results of the present study indicated that EGF promoted the proliferation of epithelial cells in the mouse tooth germs in organ culture, but also suggested that IGF-I did not stimulate the proliferation of epithelial cells in the mouse tooth germs. Less