Colchicine inhibition of casein induced amyloidosis in mice

A group of 60 Swiss mice were given daily s.c. injections of 0.5 ml 13% vitamin free solution in 0.05 N NaOH for 13 consecutive days. Of these, 20 received concomitant daily i.p. injections of 0.02 mg colchicine in 0.5 ml 0.9% NaCl solution and 15 received 0.01 mg colchicine. The remaining 25 mice served as controls and received i.p. injections of 0.5 ml 0.9% NaCl solution. On the 14th day, all animals were weighed and prepared for histologic examination. Amyloid deposits were sought by polarization microscopy after Congo red hematoxylin staining. The experiment was repeated with new batches of casein and colchicine. Thirty mice were treated with casein for 13 days. Of these animals, 20 received 0.02 mg colchicine concomitantly and 10 served as controls. In addition, 7 mice were treated with both casein and 0.02 mg colchicine for 18 days. Amyloid was not found in any of the 47 mice which received daily doses of 0.02 mg colchicine regardless of whether the experiment was terminated after 13 or 18 days. Microscopic deposits of amyloid were found in 2 of the 15 mice which received the smaller dose of 0.01 mg colchicine; the rest were amyloid free. The weight of the spleens of the colchicine treated animals ranged from 0.26 to 0.33 g. Large perifollicular deposits of amyloid were observed in the spleens of all the animals in the control group. The spleens of the control mice were markedly enlarged, weighing from 0.63 to 0.87 g.