ABSTRACT
Objective:To explore the correlation between the occurrence of colorectal cancer and different internal environment （cold and heat）. Method:The 70 Wistar rats （male and female） were randomly divided into blank group （10 cases）， cold model group （30 cases） and heat model group （30 cases）. The cold syndrome model was made by intragastric infusion of cold water （0 ℃） and soaking in cold water （10 ℃）. The heat model was made by ethanol （30%） and capsaicin solution （0.9 g·L-1）. The blank group was given normal saline by gavage， 10 mL·kg-1·d-1， for 5 consecutive weeks. The colorectal cancer model was made by subcutaneous injection of DMH solution in the back of neck in the cold model group and heat model group at the 6th week， 25 mg·kg-1，once a week，for 12 consecutive times. During the carcinogenesis， only 30% ethanol solution was given to the heat model group， and the modeling was maintained in cold model group， 10 mL·kg-1·d-1， for 38 weeks. The general state of the rats in each group was observed， and the changes of food intake and body weight were measured. At the 27th， 29th， 32th， 35th and 38th weeks， samples were collected in batches. Intestinal tissues were subjected to hematoxylin-eosin staining （HE） and detection of sodium， potassium-adenosine triphosphate （Na+ K+-ATP）， calcium， magnesium-adenosine triphosphate （Ca2+ Mg2+-ATP） activity， lactate dehydrogenase （LDH） activity and succinate dehydrogenase （SDH） activity. Result:The symptoms of hematochezia and ascites in cold model group were earlier than those in heat model group. As compared with the blank group， the food intake and body weight were decreased in cold model group and heat model group. As compared with the blank group， the length of the large intestine was shorter in cold model group at the 32nd and 35th week （P<0.05）， the activities of Na+ K+-ATP， Ca2+ Mg2+-ATP increased significantly in heat model group at the 27th， 29th and 38th week （P<0.05， P<0.01）， the SDH enzyme activity was decreased in the cold model group at the 29th and 35th week （P<0.05， P<0.01）， the SDH enzyme activity was significantly increased in the heat model group at the 38th week （P<0.01）. At the 27th week， LDH enzyme activity was significantly reduced in cold model group （P<0.01）. The LDH activity was increased significantly in heat model group at 29th and 32nd week （P<0.05， P<0.01）. As compared with the heat model group， the large intestine texture of the cold model rats showed greater brittleness， aggravated fibrosis， more obvious fibroproliferative characteristics， higher tumor incidence， and more serious tumor differentiation. The Na+ K+-ATP， Ca2+ Mg2+-ATP enzyme activities of the cold model rats were significantly reduced at 27th， 29th， and 38th weeks （P<0.01）， the SDH enzyme activity was significantly reduced in the cold model rats at 29th and 38th weeks （P<0.01）， the LDH activity was reduced in the cold model group at 32nd week （P<0.05）. Conclusion:Cold environment for colorectal cancer promotes tumorigenesis， and the hot environment can also promote tumorigenesis in a later stage.
ABSTRACT
Objective To set up a living mice colonoscopy platform to establish an orthotopic model of colorectal cancer in mice under direct vision,and to observe its biological behavior such as metastasis.Methods Eighteen-week-old male C57/BL mice were anesthetized,and the intestinal lumen of the mice was examined by a self-developed living mice colonoscopy and Olympus URF-P5 ureteroscopy,respectively.The imaging effects of the two methods were compared.Human colon cancer HT-29 cells were injected into the colonic mucosa of BALB/c-nu mice under direct vision.The colonoscopy was performed on the 3rd,7th and 15th day after the injection to observe the tumor formation in the intestinal lumen.The mice were sacrificed when the body weight decreased significantly or cachexia appeared,and then the abdominal cavity was examined including the tumor formation and metastasis.Results The self-developed living mice colonoscopy platform can provide clear vision of enteric cavity,and no mice died in the colonoscopy examination.In vivo subcutaneous injection of HT-29 cells in mice was performed with a perforation rate of 15％,a mortality rate of 33.3％,a tumor formation rate of 62.5％,an abdominal metastasis rate of 60％,a liver metastasis rate of 25％,and an abdominal wall transfer rate of 25％.Conclusion The self-developed mice colonoscopy platform can be used for the study of colorectum in living mice.The imaging effect is no less than that of Olympus URF-P5 ureteroscopy.In addition,an orthotopic colorectal cancer model can be established by this platform combing with submucosal injection technology.