AN INVESTIGATION OF THE EFFECT OF ANTI-INFLAMMATORY AND ANTI-RHEUMATOID DRUGS IN CELL-MEDIATED IMMUNE ARTHRITIS IN GUINEA-PIGS BY MICROFOCAL RADIOGRAPHY

  • 1 January 1980
    • journal article
    • research article
    • Vol. 61  (3) , 296-302
Abstract
Guinea pigs were sensitized by intra-articular injection of Mycobacterium tuberculosis (2.0 mg) into 1 knee joint and arthritis induced in the opposite knee 21 days later by intra-articular injection of antigen (0.2 mg). The time course of the arthritic changes was followed for 25 days by assessment of knee swelling and hind-limb flexion. At 28 days after challenge, the experiment was terminated and radiographic changes evaluated by means of a microfocal X-ray unit. The effect of treatment with the antirheumatic drugs, D-penicillamine (100 mg/kg by mouth), dexamethasone (0.1 mg/kg i.p.), aspirin (100 mg/kg by mouth), chloroquine phosphate (30 mg/kg by mouth) and sodium aurothiomalate (2 mg/kg i.m.) given daily from 10 days after sensitization until 28 days after challenge was assessed. Changes in joint swelling and hind-limb flexion were maximal 1-3 days after challenge. None of the drug treatments influenced these parameters. Microfocal radiography showed marked changes in arthritic animals of all X-ray parameters measured. It was possible readily to identify joint erosion, trabecular loss and associated osteoporosis, the latter occurring proximal to and relatively remote from the affected joint. No treatment prevented the radiographic changes, but exacerbation of trabecular number in the area of the epiphysis was seen with aspirin and D-penicillamine and of trabecular density further up the shaft of the femur was seen with D-penicillamine. The changes with D-penicillamine may reflect the potentiation of cell-mediated hypersensitivity with this drug reported by other workers. The model is not suitable for the detection of clinically active antirheumatic drugs but microfocal radiography provides a sensitive index for the assessment of joint damage in small animals.