Abstract
In order to investigate the effects of mecobalamin on experimental carcinomatous neuropathy, hepatoma-bearing rats were produced by chronic feeding of 3'-methyl 4-dimethylaminoazobenzene (3'-Me-DAB), and neuropathy was quantitatively evaluated by the motor nerve conduction velocity (MCV) of the dorsal nerve trunks.
The rats were kept feeding on Oriiental Solid Food containing 0.06% 3'-Me-DAB until 12 weeks after the start of the experiment when hepatoma was confirmed to develop and 500μg of mecobalamin injection was initiated twice a week. At 17 and 23 weeks with an interval of 2 weeks after the last injection, MCV and serum B12 level were measured. The MCV's of vitamin B12-treated hepatoma rats were not reduced at 17 weeks as compared with untreated hepatoma-bearing rats although in the later stage the difference between the two groups was not remarkable. It was quite reasonable that the serum vitamin B12 levels were low in the control hepatoma rats while those of vitamin B12-treated hepatoma rats were high. However, interesting enough, a positive correlation was observed between MCV and serum vitamin B12 level in the control hepatoma rats.
From the above results, it was suggested that vitamin B12 deficiency may at least one of the causes of neuropathy in hepatoma-bearing rats, and vitamin B12 administration could prevent carcinomatous neuropathy.