Comparison of lung cancer and amyloidosis in rabbits induced by chemical carcinogens.

For the purpose of inducing experimental lung cancer, carcinogens were applied into the bronchus of the rabbit. Experiments were divided into 2 groups, I and II, depending on the methods of application of chemical carcinogens into the bronchus. In Experiment I, carcinogens (4-nitroquinoline 1-oxide and/or 3-methylcholanthrene) in rabbit plasma or distilled water were instilled in the lower bronchus and, in Experiment II, 3-methylcholanthrene in Tween 60 was swabbed on the maon bronchus through a specially made bronchoscope. (1) In Experiment I, 163 of 366 rabbits having received over 4 instillations of the chemical carcinogens and surviving for more than 30 days developed lung cancer. However, in Experiment II, only 2 of 65 rabbits surviving more than 60 days developed lung cancer. (2) In Experiment II, 39 (60%) of 65 rabbits were found to have developed amyloidosis. However, in Experiment I, 86 (approx. 23%) of 366 rabbits developed amyloidosis. Amyloidosis was observed to occur in the kidneys, spleen, liver, and adrenals in both experiments.