Stevens R H, Loven D P, Osborne J W, Prall J L
Cancer Lett. 1978 Jun;4(6):325-32. doi: 10.1016/s0304-3835(78)95557-x.
The intracellular concentrations of adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) were determined in adult male Holtzman rat small intestinal tumors induced by subcutaneous administration of 1,2-dimethylhydrazine (DMH) or X-irradiation of only the hypoxic ileum and jejunum. The levels of cAMP and cGMP in the cancer cells from DMH-treated animals were 50% and 200%, respectively, of the values measured for intestinal tissue. The amounts of cGMP in the lesion of the X-irradiation induced rat small bowel adenocarcinoma determined in the present investigation and of cAMP measured previously were observed to be only 50% of the value for unirradiated intestine. It has thus been shown that in the DMH-induced colon and small intestinal tumors, the X-irradiation induced rat small bowel adenocarcinoma and the human colon adenocarcinoma, the cAMP concentrations are consistently about 50% of the levels measured in comparable normal tissues. These findings of diminished intracellular cAMP concentrations imply a serious cellular defect mechanism occurring in intestinal cancer. However, there appears to be no similar pattern of change for the intracellular concentrations of cGMP, which suggests that different biochemical pathways exist in these malignancies.
通过皮下注射1,2 - 二甲基肼（DMH）或仅对缺氧的回肠和空肠进行X射线照射，诱导成年雄性霍尔茨曼大鼠发生小肠肿瘤，然后测定其细胞内3',5'-环磷酸腺苷（cAMP）和3',5'-环磷酸鸟苷（cGMP）的浓度。DMH处理动物的癌细胞中cAMP和cGMP的水平分别为肠组织测量值的50%和200%。在本研究中测定的X射线照射诱导的大鼠小肠腺癌病变中的cGMP量以及先前测量的cAMP量，仅为未照射肠组织值的50%。因此表明，在DMH诱导的结肠和小肠肿瘤、X射线照射诱导的大鼠小肠腺癌以及人类结肠腺癌中，cAMP浓度始终约为可比正常组织中测量水平的50%。细胞内cAMP浓度降低的这些发现意味着在肠道癌症中发生了严重的细胞缺陷机制。然而，cGMP的细胞内浓度似乎没有类似的变化模式，这表明这些恶性肿瘤中存在不同的生化途径。
