Specificity of urinary excretion of cross-linked N-telopeptides of type I collagen as a marker of bone turnover

摘要: Urinary excretion of cross-linked N-telopeptide type I collagen (NTX) has been reported to be a specific indicator bone resorption. We studied the utility new immunoassay for NTX as an changes in resorption caused by treatment with pamidronate (APD) followed T3. Twenty-two male subjects received either placebo (Group 1) or APD on study days 1–2 2). One week later all T3 100 μg/day (days 8–15). NTX, pyridinoline (PYD), hydroxyproline (HYP), and creatinine (cr) were measured 2-hour fasting urine samples at baseline (day 1), after APD/placebo 8), 16), 30 58. NTX/cr fell 85% (P<0.001 versus baseline), but not placebo. The fall mean urinary receiving was greater than PYD (25%) HYP (31%) HYP). After APD, remained suppressed below until day 58, whereas returned 16. Persistence APD's effect 58 suggested fact that serum calcium parathyroid hormone levels had On 16, treated T3, rose significantly (P<0.01) Group 1 (-bisphosphonate) 2 (+bisphosphonate). conclude is responsive acute thyroid hormone-induced increases bisphosphonate-induced decreases resorption, may reflect these more accurately HYP.