Kossoy G, Ben-Hur H, Popovich I, Zabezhinski M, Anisimov V, Zusman I
Laboratory of Experimental Oncology, Koret School of Veterinary Medicine, Faculty of Agricultural, Food and Environmental Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
Oncol Rep. 2000 Nov-Dec;7(6):1401-5. doi: 10.3892/or.7.6.1401.
The suppression of 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis by melatonin was previously demonstrated. The objective of the present work was to evaluate histologically and immunohistochemically the splenic immune response to the induced cancer and to melatonin. Spleens from rats, either untreated, injected with DMH, fed with melatonin or treated with both carcinogen and melatonin, were studied. The exposure to the carcinogen and the consequential carcinogenesis resulted in splenic changes that reflected the insufficiency of the immune response, as manifested in significant reduction of the white pulp and the simultaneous expansion of the red pulp. The effects of melatonin on most splenic components were inverse to those of DMH. The anti-carcinogenic properties of melatonin were evidenced from the reversal of the inhibitory effects of DMH, especially when the densities of lymphocytes in different parts of the spleen were compared. The combined treatment of the rats with DMH and melatonin resulted in the expansion of the splenic zones by 106% to 125%, compared to those from DMH-treated rats, and the numbers of CD8+ lymphocytes and Fas-positive cells increased sharply. Therefore we conclude that anti-carcinogenic effects of melatonin are related to activation of several elements of the host's lymphatic system.
褪黑素对1,2 - 二甲基肼（DMH）诱导的结肠癌发生具有抑制作用，这一点此前已得到证实。本研究的目的是通过组织学和免疫组织化学方法评估脾脏对诱导产生的癌症以及褪黑素的免疫反应。对未处理、注射DMH、喂食褪黑素或同时接受致癌物和褪黑素处理的大鼠的脾脏进行了研究。暴露于致癌物及由此引发的癌症导致脾脏发生变化，反映出免疫反应不足，表现为白髓显著减少，同时红髓扩张。褪黑素对大多数脾脏成分的影响与DMH相反。从DMH抑制作用的逆转情况可以证明褪黑素的抗癌特性，尤其是比较脾脏不同部位淋巴细胞密度时。与DMH处理的大鼠相比，DMH和褪黑素联合处理的大鼠脾脏区域扩大了106%至125%，CD8 + 淋巴细胞和Fas阳性细胞数量急剧增加。因此我们得出结论，褪黑素的抗癌作用与宿主淋巴系统多个元素的激活有关。
