Comparative effects of aminotriazole on normal and acatalasemic mice.

Some pharmacological and toxicological effects of dietary 3-amino-1,2,4-triazole (AT), a known catalase inhibitor, antithyroid agent, and carcinogen, have been examined, using acatalasemic (Csb) and normal catalase, "wild-type" (Csa) substrains of highly inbred C3H and C57BL mice. It was found that (a) the acatalasemic substrains are more resistant to weight loss and death on the AT diet than are their normal catalase counterparts; (b) Csb and Csa substrains of C57BL mice are more resistant to weight loss and death on the AT diet than are the Csb and Csa substrains of the C3H mouse; (c) the liver catalase, as well as the whole body catalase, of the two C57BL substrains is less inhibited by the AT diet than is that of the C3H substrains; (d) mice consuming the same quantity of either normal or AT-containing diet gain much more weight on the normal diet; (e) temporary consumption of the AT diet causes a considerable increase in thyroid weight, with an extremely slow, and only partial, return toward normal weight; and (f) the C3H/Csa mouse on an AT diet develops a scaly, necrotic tail very similar in appearance to the so-called rodent ringtail; this lesion is never observed in the acatalasemic mouse on the same diet.