目的研究大肠癌患者血清及癌细胞内促胃液素（Ｇａｓ）水平及临床意义．方法采用ＲＩＡ法检测３５例大肠癌患者血清和癌细胞及癌旁粘膜细胞内Ｇａｓ水平．结果大肠癌患者术前、术后血清Ｇａｓ水平与对照组无显著差异（Ｐ＞００５），根治术后明显低于术前（２９ｎｇ／Ｌ±５ｎｇ／Ｌｖｓ３５ｎｇ／Ｌ±１２ｎｇ／Ｌ，ｔ＝２７７２，Ｐ＜００１），在高分化（３６ｎｇ／Ｌ±１６ｎｇ／Ｌｖｓ２８ｎｇ／Ｌ±５ｎｇ／Ｌ）和中分化腺癌组中（３８ｎｇ／Ｌ±７ｎｇ／Ｌｖｓ２７ｎｇ／Ｌ±３ｎｇ／Ｌ）差异显著（ｔ＝２１５２和２３５６，Ｐ＜００５）．大肠癌细胞内Ｇａｓ水平明显高于癌旁３ｃｍ和６ｃｍ粘膜（２１３ａｇ／细胞±７２ａｇ／细胞ｖｓ１４７ａｇ／细胞±３６ａｇ／细胞，１３９ａｇ／细胞±３２ａｇ／细胞；ｔ＝４８９１和５６１３，Ｐ＜００１）和正常粘膜（１３６ａｇ／细胞±４６ａｇ／细胞；ｔ＝２５３４，Ｐ＜００５），高分化腺癌明显高于低分化和粘液腺癌（２４１ａｇ／细胞±７８ａｇ／细胞ｖｓ１６１ａｇ／细胞±４６ａｇ／细胞，ｔ＝２５０５，Ｐ＜００５）．结论大肠癌细胞可通过自分泌方式分泌Ｇａｓ，Ｇａｓ升高是大肠癌分化良好的标志 Objective To study the level of gastrin (Gas) in serum and cancer cells of patients with colorectal cancer and its clinical significance. Methods RIA method was used to detect the level of Gas in serum and cancer cells and paraneoplastic mucosa in 35 patients with colorectal cancer. Results There was no significant difference in preoperative and postoperative serum Gas levels between patients with colorectal cancer and the control group (P>0.05), and it was significantly lower than that before surgery (29ng/L±5ng/L vs. 35ng/L±12ng/L, t). =2772, P<001), in well differentiated (36ng/L±16ng/Lvs28ng/L±5ng/L) and moderately differentiated adenocarcinoma group (38ng/L±7ng/Lvs27ng/L±3ng/ L) Significant difference (t=2152 and 2356, P<005). The Gas levels in colorectal cancer cells were significantly higher than those in the paracancerous 3cm and 6cm mucosa (213ag/cell ± 72ag/cell vs147ag/cell ± 36ag/cell, 139ag/cell ± 32ag/cell; t = 4891 and 5613, P <001) and normal mucosa (136ag/cell ± 46ag/cell; t=2534, P<005), well-differentiated adenocarcinoma was significantly higher than that of poorly differentiated and mucinous adenocarcinoma (241ag/cell ± 78ag/ Cells vs161ag/cell ± 46ag/cell, t=2505, P<005). Conclusion Colorectal cancer cells secrete Gas by autocrine, and elevated Gas is a sign of good differentiation of colorectal cancer.