Jaskiewicz K, Kritchevsky D, Venter F S, van Wyk W E
Br J Exp Pathol. 1987 Jun;68(3):439-51.
The study was designed to identify diet and carcinogen-dependent ultrastructural changes in the epithelium of macroscopically normal colonic mucosa in primates. Seventy adult female vervet monkeys were divided into seven equal treatment groups. Four received a Western high-fat low fibre diet (WD), two a prudent low-fat higher fibre diet (PD) and one a control low-fat high fibre diet (CD). Three groups (2 WD, 1 PD) received dimethylhydrazine intramuscularly at 14 day intervals. After 18 months, monkeys of two groups on the WD were transferred to the PD (WD----PD) and 30 months later all were killed. Mucosae of caecum, colon transversum and rectum were examined by scanning and transmission electron microscopy and showed close similarity to that of humans. Rectal mucosae showed increased surface goblet cell secretory activity, mucin production and microvillar changes related to WD and WD----PD. The enhancing effect of a carcinogen on ultrastructural changes such as cellular pleomorphism, cytoplasmic interbridging, nuclear and nucleolar irregularities and appearance of argentaffin cells in the free surface epithelium were noted predominantly in high-fat treated animals. Such changes observed in the upper part of crypt, orifice and free surface epithelium can be characteristic for precancerous change and could be utilised practically in the detection of precursor lesions of the colon.
该研究旨在确定灵长类动物宏观正常结肠黏膜上皮中饮食和致癌物依赖性的超微结构变化。70只成年雌性绿猴被分为7个相等的治疗组。4组接受西方高脂肪低纤维饮食（WD），2组接受谨慎的低脂肪高纤维饮食（PD），1组接受对照低脂肪高纤维饮食（CD）。3组（2组WD，1组PD）每隔14天肌肉注射二甲基肼。18个月后，两组WD饮食的猴子被转移到PD饮食组（WD→PD），30个月后全部处死。通过扫描和透射电子显微镜检查盲肠、横结肠和直肠的黏膜，发现其与人类的黏膜非常相似。直肠黏膜显示出与WD和WD→PD相关的表面杯状细胞分泌活性增加、黏蛋白产生和微绒毛变化。致癌物对超微结构变化的增强作用，如细胞多形性、细胞质桥接、核和核仁不规则以及游离表面上皮中嗜银细胞的出现，主要在高脂肪处理的动物中观察到。在隐窝上部、开口和游离表面上皮中观察到的这种变化可能是癌前变化的特征，并且在结肠前体病变的检测中具有实际应用价值。
