EFFECT OF LESION SIZE ON THE METABOLIC-ACTIVITY OF TIBIAL DYSCHONDROPLASTIC CHONDROCYTES

Experiments were conducted to determine the influence of lesion size a nd method of producing tibial dyschondroplasia on metabolic activity o f cultured chondrocytes. Genetic selection was one method used to prod uce a high incidence of tibial dyschondroplasia. Chondrocytes obtained from severe lesions exhibited reduced mitogenic activity (H-3-thymidi ne incorporation) and ability to synthesize matrix proteoglycans ((SO4 )-S-35 incorporation) when compared with normal growth plate and small er lesions. When a commercial broiler strain was used, all chondrocyte s isolated from lesions induced by feeding thiram had reduced metaboli c activity. Similar results were observed with severe lesions obtained from copper-deficient chicks. It is concluded that lesion size is an important factor in determining subsequent metabolic activity of chond rocytes isolated from tibial dyschondroplastic lesions.