Effect of vitamin A on epitheliomesenchymal interaction during odontogenesis and oncogenesis in NMU-treated hamster.

维生素 A 对 NMU 处理的仓鼠牙发生和肿瘤发生过程中上皮间充质相互作用的影响。

• 批准号: 03670842
• 负责人: KOHGO Takao
• 金额: $ 1.28万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03670842/
• 关键词: Vitamin A; Disturbances in odontogenesis; Odontogenic tumor; Epitheliomesenchymal interaction; Oncogenesis; N-nitrosomethylurea; Retinol palmitate; beta-carotene; 歯肉腫瘍; 歯の形成異常; ハムスター; 上皮ー間葉相互作用; 上皮ー関葉相互作用; Nーニトロソメチルウレア

1) NMU-induced disturbances in odontogenesis of the cut mandibular incisors was hypoplasia ranging in extent from loss of pigment of enamel and enamel hypoplasia to loss of enamel and irregular hypoplastic dentin formation. These changes of the incisors were more prominent in animals treated with retinol palmitate (RP) plus NMU than those in the animals treated with NMU alone.2) When RP was administered in combination with NMU,there was an increase frequency of odontogenic epithelial cell nests' proliferation with dysplastic dentin formation at the incisal region.3) In RP plus NMU-treated hamsters, the frequency and degree of neoplastic changes of the odontogenic epithelium with dentin formation were increased.4) In NMU-treated hamsters, an excess of beta-carotene slightly prevented the disturbances in odontogenesis, atypical proliferation of odontogenic epithelium, and keratinization of epithelial component.5) NMU inhibited ameloblast differentiation, whereas, the differentiation of odontoblasts and cell-to-cell contact between preameloblasts and odontoblasts were not prevented. RP and beta-carotene did not prevent NMU-induced inhibition of ameloblast differentiation but inhibited NMU-induced keratinization of odontogenic epithelium. Atypical proliferation of odontogenic epithelium with inductive dentin formation caused by RP + NMU treatment resulted from the inhibition of squamous metaplasia with keratinization of the epithelium.6) RP plus NMU treatment resulted to a decrease in incidence of neoplastic invasion of the epithelium in the gingiva or forestomach.7) beta-carotene has moderate suppressive effect on tumor growth of the gingival squamous cell carcinoma and slight effect on squamous cell carcinoma of the forestomach.8) Administration of large quantity of beta-carotene induced adenofibrosislike proliferation of the bile ducts and proliferation of spindle-shaped cells in the submucosa of the glandular stomach in NMU-treated hamsters.

1)NMU诱导的下颌切牙牙发育障碍是发育不全，其程度从釉质色素损失和釉质发育不全到釉质损失和不规则发育不全牙本质形成。结果表明：1）当RP与NMU联合应用时，牙源性上皮细胞巢的增殖频率增加，牙本质发育不良; 2）当RP与NMU联合应用时，牙源性上皮细胞巢的增殖频率增加，牙本质发育不良; 3）在RP与NMU联合应用的仓鼠中，牙源性上皮的肿瘤性变化的频率和程度随着牙本质形成而增加。4）在NMU处理的仓鼠中，过量的β-胡萝卜素轻微地防止了牙源性上皮的紊乱，牙源性上皮的非典型增殖，5）NMU抑制成釉细胞的分化，但不能阻止成牙本质细胞的分化以及成釉细胞与成牙本质细胞之间的细胞接触。RP和β-胡萝卜素不能阻止NMU诱导的成釉细胞分化抑制，但能抑制NMU诱导的牙源性上皮角化。RP + NMU治疗引起的牙源性上皮的非典型增殖和诱导性牙本质形成是由于上皮角化引起的鳞状上皮化生的抑制。6）RP + NMU治疗导致牙龈或前胃上皮肿瘤侵袭的发生率降低。7）β-胡萝卜素对牙龈鳞状细胞癌的肿瘤生长具有中等抑制作用，对前胃鳞状细胞癌具有轻微抑制作用。胡萝卜素诱导腺纤维样增生的胆管和增殖的梭形细胞在粘膜下层的腺胃在NMU处理的仓鼠。