目的观察甲基硝基亚硝基胍（ＭＮＮＧ）诱发Ｗｉｓｔａｒ大鼠胃腺癌（ＧＣ）和癌前病变（ＰＬ）过程中外周血淋巴细胞（ＰＢＬ）微核率（ＭＮＦ）的动态变化及大蒜的影响．方法ＭＮＮＧ组（ＭＧ）３０只，预防组（ＰＧ）３０只与治疗组（ＴＧ）２０只给予ＭＮＮＧ１２５ｍｇ／５ｍｌ／ｄ诱发大鼠ＧＣ及ＰＬ，ＰＧ另给１０％大蒜（ＧＪ）１０ｍｌ／ｄ．１０个月后，ＰＧ与ＴＧ继续给１０％ＧＪ１０ｍｌ／ｄ，对照组（ＣＧ）与ＭＧ饮自来水，至１６个月．运用微核细胞培养技术，动态检测各组ＰＢＬ微核率．结果ＧＣ与ＰＬ的ＭＮＦ各为１８１±８４和９７±５３，均显著高于ＣＧ的１９±０９（Ｐ＜００１），ＰＬ低于ＧＣ（Ｐ＜００１），而粘膜内癌（ＩＭＣ）与浸润癌（ＩＣ）差异无显著性．ＭＧ１０个月（２４２±８８）与１６个月时（２１３±６８）无明显差异，但始终比ＣＧ高（Ｐ＜００１）．ＰＧ１０个月（１５３±８１）比１６个月时（９３±４１）高（Ｐ＜００１），并和ＴＧ（１０８±５６）皆低于ＭＧ，而ＰＧ与ＴＧ区别无意义．结论ＭＮＮＧ诱发大鼠胃癌的致突变和致癌变性作用持续．大蒜具有明显的抗突变和癌变的效果．ＭＮ先于胃癌出现于癌前病变? Objective To observe the dynamic changes of micronuclear rate (MNF) of peripheral blood lymphocytes (PBL) in the process of gastric adenocarcinoma (GC) and precancerous lesion (PL) in Wistar rats induced by methylnitrosoguanidine (MNNG) and garlic influences. METHODS: Thirty MNNG patients (MG), 30 prophylactic patients (PGs) and 20 treatment patients (TGs) received MNNG125mg/5ml/d to induce rat GC and PL, and PG supplemented with 10% garlic (GJ) 10ml/ d. After 10 months, PG and TG continued to give 10% GJ 10ml/d, control group (CG) and MG to drink tap water, to 16 months. Using micronuclear cell culture technology, dynamic detection of micronuclear rate of PBL in each group. Results The MNF of GC and PL were 181±84 and 97±53, respectively, which were significantly higher than that of CG of 19±09 (P<001). The PL was lower than that of GC. P<001), but there was no significant difference between intramucosal cancer (IMC) and invasive cancer (IC). There was no significant difference in MG 10 months (242±88) and 16 months (213±68), but it was always higher than CG (P<001). PG 10 months (153±81) were higher than those at 16 months (93±41) (P<001), and TG (108±56) were both lower MG, and the difference between PG and TG is meaningless. Conclusion The mutagenic and carcinogenic effects of MNNG-induced gastric cancer continue. Garlic has obvious anti-mutation and cancerous effects. MN precedes gastric cancer in precancerous lesions?