AGE-RELATED-CHANGES IN THE PYRIDINOLINE CONTENT OF GUINEA-PIGS CARTILAGE AND ACHILLES-TENDON COLLAGEN

Age-related changes of pyridinoline, a mature cross-link of collagen f ibers, in tissues of guinea pigs which cannot synthesize L-ascorbic ac id (AsA) were investigated. Male guinea pigs, 2 weeks old, were fed a commercial diet until they were 40 weeks old. Based on the data of bod y weight gain, it is assumed that guinea pigs require 10 weeks to reac h maturity. The content of AsA in serum, adrenals, and liver of the an imals increased with growth, then decreased after 8-10 weeks. The pyri dinoline content in cartilage and tendon collagen was very low in 2-we ek-old animals, whereas it increased markedly with growth. After 10 we eks, the pyridinoline tended to decrease in cartilage collagen; howeve r, it was not changed in tendon collagen. The age-related changes of p yridinoline content in guinea pigs cartilage were similar to those of humans-increasing with growth and decreasing after adolescence.