Changes in urinary excretion of type-I collagen cross-linked C-telopeptide and N-telopeptide in perimenopausal women.

In order to assess the dynamics of bone turnover during menopausal transition, we measured the urinary excretion of C-telopeptide (CTX) and N-telopeptide (NTX) of type-I collagen, new markers of bone resorption, using two ELISAs which recognize the corresponding cross-linked peptide of type-I collagen. CTX and NTX levels in postmenopausal women were significantly higher than those in premenopausal women, confirming the enhancement of bone resorption after menopause. The measurement of CTX and NTX, which is convenient and specific for bone resorption compared with conventional bone resorption markers, pyridinoline and deoxypyridinoline, might be useful in the management of postmenopausal women.