The Effect Of Thermal Damage On The Carcinogenesis Of Esophageal Squamous Cell Carcinoma Induced By 4-nitroquinoline-1-oxide

Objective:The purpose of this study is to research the suitable gavage needle longth when to gavage C57BL/6 mouse;Thermal damage and repair of C57BL/6 mice esophagus by distilled water at 75?;If he can accelerate the cancer process induced by 4NQO if we stimulate the esophagus by75? hot water long time and multi-frequency.Methods:1 By measuring the body length of C57/BL6 mice with different body weights,the distance of owner incisors from the upper edge of the aortic arch edge,the distance of Lower incisors,to obtain the esophageal length parameters under certain conditions,to select the appropriate parameters for the depth of needle insertion.2 After one time of gavage by 0.2ml and 75?sterilized distilled water,at 12 hours,48 hours,72 hours,three time points,the mice were euthanized,histopathological observation of the esophagus under the aortic arch.3 Using 75 degrees of heat sterilization distilled water 0.2ml,get a one time of gavage every 48 hours,As thermal injury group.Let mice freely drink water which contained 4NQO of 100?g/mL combined with gavage of ordinary temperature sterilized distilled water 0.2ml every 48 hours,as the cancer inducing group.Using water contained 4NQO100?g/mLd,union 0.2ml of sterilization distilled water which is 75? to gavage mice every 48 hours,as the combined induction group.The pathological changes of esophagus of C57BL/6 mice were observed at8,12,16,19,21 weeks.Results:1 the mice Body weight and body length,the distance of Incisor from the lower edge of the aortic arch,the distance of incisors from diaphragm plane,there is no obvious correlation between each other.the distance of incisors from diaphragm plane's,((?)±S)is 28.3±1.41.2 C57BL/6 mice can withstand 75 degrees of heat damage,damage is mostly confined to the mucosa,rare basal cell damage,12 hours after heat injury,the pathological Performance as: first degree burn,48 hours after the heat injury the esophagus has shown a tendency to repair,however,there were obvious cell edema and inflammatory cell infiltration,and this performance is more serious than 12 hours,72 hours later,the esophageal mucosa was repaired,jhowever,there is still a small amount of lymphocyte infiltration in the esophagus,except of this no obvious abnormality can be seen.3 The simple cancer inducing group,at 16 weeks,esophageal mucosa showed atypical hyperplasia,19 weeks of carcinoma in situ,21 weeks the mice canceration rate was 100%.5 of the mice cancer cells infiltrated into the muscularis,ten mices cancer cells infiltrated into the submucosa.Heat damage and carcinogen group: the third degree of atypical hyperplasia was seen in 12 weeks,16 weeks can seen early canceration,At 19 and 21 weeks,the esophageal carcinoma showed infiltration,The canceration rate was 100,at 21 weeks,six mice were infiltrated into the myometrium,six mice infiltrated into submucosa,from the 16 week,the esophageal mucosa of the mice in the heat injury group showed a simple hyperplasia.But until the end of the experiment,there was no carcinogenesis in mice with heat injury,at 21 weeks,have 4 mice showed moderate hyperplasia,fourteen mices showed mild hyperplasia.Conclusions:1 The distance of from the aortic arch incisors to the lower edge of the average is about 28 mm,it is a suitable depth of needle insertion,the depth of insertion of intragastric injection needle placement 28 mm,can basically guarantee,every time the Esophageal below aortic arch will be damaged when gavaged.2 Gavage mice by distilled water at 75 degrees centigrade 0.2ml,can cause acute injury of esophageal mucosa in mice,it is bing confirmed by the pathological performance after 12 hours of gastric lavage.48 hours after injury for 75?,the esophageal mucosa of mice cannot complete repair,obvious inflammatory cell infiltration Still can see.72 hours later,the mice esophageal mucosa were almost normal.3 Chronic thermal injury of mouse esophagus induced by repeated stimulation at 75?,Can accelerate the process of 4NQO induced cancer,Although to the end of the experiment the only 75 degrees of thermal damage.Failed to induce esophageal carcinogenesis in mice,However,it has not been proved that pure thermal injury will not lead to carcinogenesis.