Prolonged treatment with D-penicillamine: effects on adjuvant arthritis in the rat.

The effects of long term D-penicillamine treatment on adjuvant arthritis in the rat were determined in order to establish a possible approach to the laboratory evaluation of anti-rheumatic drugs. Oral pretreatment (1-3 months) followed by continued through-treatment on a daily basis (100 mg/kg p.o.) failed to modify the parameters tested: viz. (a) body weight changes; (b) primary paw lesions; (c) secondary hind paw lesions; (d) secondary forepaw, ear and tail lesions; (e) the number of 'responders'. Autopsy showed no macroscopic abnormalities in the lungs, heart, thymus, liver, spleen, adrenal glands, kidneys and gastro-intestinal tract. These results are discussed in relation to previous findings whereby rat adjuvant arthritis, in addition to other experimental immune reactions, has been suggested as an indicator for D-penicillamine activity.