<p>The changes of taste buds of the rabbit foliate papillae induced by the administration of Bleomycin (BLM) were observed under optical and electron microscopes. Applicable dosage for human body represents 0.3mg/kg while 5 times as much as used for the first BLM administration. The rabbits used in these experiments were grouped into two groups with one administrated only once while the other was administrated continuously in the range of 5 through 10 times in 24 hours intervals. Examinations on taste buds for the total of 35 rabbits were undertaken after 60 minutes, 24 hours, 7th day, 10th day, 20th day and 30th day of the BLM administration. The results of the experiments are as follows : Optic microscopical findings : 1. Taste cells were almost identical as normal cells with little changes being observed after 60 minutes of the first BLM administration. However, many taste buds were penetrated by leucocyte as a resulting abnormal phenomenon of the BLM administration. 2. Major changes took place in type II cells after 24 hours of the first BLM administration. The degeneration of cells was found in the forms of vacuolization of cytoplasm and distortion of nucleus, however, the number of transformed cells decreased in course of days. 3. The changes were also observed in type I cells after 24 hours of continuous BLM administration, i.e., atrophy of cytoplasm as well as distortion of nucleus being attended with an increase in the size of intercellular space. 4. In course of time after the BLM administration was conducted, a large number of cell cleavages was witnessed around the edges of taste buds, with most of those cell cleavages moving into taste buds while they were being segmented. Electron microscope findings : 1. The vacuolization and dilation of ER and mitochondria were observed after 60 minutes of the first BLM administration. All the leucocytes penetrated into taste buds were found to be neutrophil leucocytes. 2. The appearance of degeneration of type II cells became more conspicuous while the same kind of phenomenon was taking place in type I cells. A minor degeneration in type III cells was observed with a slight increase in the amount of filament in each cell. The secondary lysosome was found in each of those cells. The cells other than type II cells became normalized after 10th days of the BLM administration. 3. Not only vacuolized-distorted cells but also the atrophy of cytoplasm and increased electron density were appeared in certain type I cells after 24 hours of continuous BLM administration. Only few r-ER and mitochondria were contained in the above-mentioned cells in which no filament and ribosome were observed. Further vacuolization and dilation were apparent in type II cells. The collapse phenomenon of cytoplasm and of nucleus took place in certain type II cells. The vacuolization of ER and mitochondoria not only appeared in type III but changes in the number of dark cored vesicle and electron density were also observed. Some changes were also found in a part of synapse. Althoush these degenerated cells became normalized with lapse of days, it was noticed that a difference exists with respect to quickness of recovery among type I, II and III cells. By order of quickness or recovery, type I recovered first with III second. However, type II possessed degenerated cells after 30 days of BLM administration. 4. Nuclear body was observed most in type II cells of which forms were classified into three types, i.e., fibrous like, round and beaded like shapes. The beaded nuclear body, especially, was discharged into cytoplasm through enlarged nuclear pores. 5. Binuclear cells were sometimes observed in type II cells. 6. There were certain type I cells of which apical cytoplasms did not form microvilli but reached to the hem of taste pores as a club like projection. To synthesize the above findings, a structual formation of type II cells was found to be most strongly</p><p>(View PDF for the rest of the abstract.)</p>