Influence of prednisolone and L-thyroxine on the changes in collagen metabolism in rats with adjuvant-induced arthritis.

In rats with adjuvant-induced arthritis the effects of prednisolone and L-thyroxine on the changes in collagen metabolism were investigated both in the skin and tendon during the acute and chronic phase of the arthritis. In untreated animals with adjuvant-induced arthritis, a decrease in the collagen synthesis accompanied by an increase in the catabolism of collagen and a retardation in the conversion of soluble to insoluble collagen were noted both in the skin and tendon during the course of the disease. Prednisolone was found to accelerate the conversion of soluble to insoluble collagen and to inhibit the enhanced catabolism of collagen in rats with adjuvant-induced arthritis. L-Thyroxine accelerated the conversion of soluble to insoluble collagen in adjuvant-induced arthritic rats more effectively than prednisolone but was less effective with regard to the inhibition of enhanced catabolism of collagen. However, the synthesis of collagen in adjuvant-induced arthritis was improved by both prednisolone and L-thyroxine.