Developing a rat model for oral mucositis induced by chemotherapy

Today, cancers, epidemics and similar diseases affect the living standards of patients and the risk of mortality due to diseases increases day by day. Although several methods are used in cancer treatment, the most commonly used one is chemotherapy treatment. The antimetabolite agents used in chemotherapy stop the growth, development and proliferation of the cells with malignant characteristics. They also affect normal cells that do not show malignant characteristics. The cells most damaged by the cytotoxic damage of chemotherapy are oral mucosal epithelial cells which have rapid division. As a result of the suppression of oral mucosa cells, the mucosal barrier is disrupted and mucositis occurs. The oral mucositis causes severe pain, difficulty in feeding, infection and a long hospital stay, and these symptoms affect the patient's treatment process negatively. The aim of this study was to create an ideal rat model that can be studied in the treatment of oral mucositis. In order to create an oral mucositis model, 4 different pilots and a main study were conducted consecutively. In the first pilot study, a total of 100 mg/kg 5-Fu was administered intraperitoneally (i.p.) to the 4 rats, but oral mucositis could not be induced. In the second pilot study, a total of 120 mg / kg 5-Fu was administered to the rats whose buccal mucosa was drawn with a needle, and this model was also unsuccessful. These rats were not sacrificed and 5-Fu administered in the 2nd cycle again as 60 mg/kg on the first day 150 mg/kg on the 3rd day, 60 mg/kg on the 5th day and acetic acid (AA) was applied by scratching the cheeks of the rats, then the oral mucositis model was successfully established. Thereupon, as a 4th study, the oral mucositis model was tried to be obtained by applying the material method of the 3rd study to the 40 rats, but all animals were lost on the 4th day. The 5th study was planned in order to make the model work fully and to prevent animal losses in other future studies, considering that the mortality depending on the dose amounts used in these studies in the literature does not reflect the reality. For this purpose, 22 adult male rats of 6 months old Sprague Dawley breed were used in this study. The rats in the study were divided into 5 different groups and all animals except 2 rats selected as the control group received 60 mg / kg on the first day and 150 mg / kg 5-Fu i.p. on the fifth day were given as and the buccal mucosa of all animals was drawn and 20% A.A. has been applied. On the 13th day, animals were sacrificed, and blood and tissue samples were taken. In the light of the findings obtained, the clinic, where the administration of 20% acetic acid (15 μl) to the buccal mucosa with 5-Fu given at doses of 60mg / kg + 150 mg / kg can cause oral mucositis and the animals can survive with low mortality data for a long time enough to be used in a study was supported by histological and laboratory findings. Keywords: Oral mucositis, Rat model, 5-Fluorouracil, Chemotherapy, Acetic acid