The effects of intra-articular 198 Au instillations on articular cartilage.

An experiment was devised to determine the effects of radiogold instillation on intra-articular tissue. Adult and weanling rats were injected with doses of 198Au ranging from 1 to 10 mCi. Radiation-induced damage to articular cartilage occurred only in wean1ing rats at extremely high doses (2.5-5 mCi). Adult rat articular cartilage is extremely resistant to radiation damage and to high doses of 198Au(5-10 mCi). Experimental evidence indicates a safety factor of 100 to 1000 X exists in the dose (1mCi/0.1 ml) used clinically for the treatment of rheumatoid arthritis.