実験的膀胱腫瘍に対する免疫学的研究

Abstract

Experimental bladder tumors were induced in rat by oral administration of BBN and investigations were performed concerning histological changes in the bladder and changes with time in the mitogen response of the lymphocytes of rats treated with carcinogen and immunostimulating agent. BBN was dissolved in deionized water as a 0.05% solution and administered, ad libitum, to the Fischer Strain Rats for 12 weeks. Levamisole was used as immunostimulating agent. 180 rats were devided to 6 groups. The first group was a control group which did not receive neither BBN nor Levamisole. The second group received BBN only and the 3-6th groups received both BBN and Levamisole. The third group received Levamisole at a dose of I mg/kg of body weight every day from 8 to 25 weeks after the beginning of experiment. The 4-6th groups received at a dose of I, 3 and 8 mg/kg every day from 12 to 25 weeks. Lymphocytes from the second group which received BBN only had a lower response to mitogen than the first group. Lymphocytes from the 3-5th groups which received low dose of Levamisole had a higher response to mitogen than the second group. These were as well as the first group. But lymphocytes from the 6th group which received high dose of Levamisole did not have an increased response to mitogen. At 25 weeks after the beginning of experiment, any animals of the first group did not develop bladder tumor, and all animals of the second and the 6th groups had bladder tumors. 43% of the third group, 27% of the 4th group and 18% of the 5th group showed no appearance of bladder tumors.