ACUTE EFFECTS OF NASAL SALMON-CALCITONIN ON CALCIUM AND BONE METABOLISM

Effects of a single dose of 200 IU of nasal salmon calcitonin (SCT) on calcium metabolism and biochemical markers of bone turnover were inve stigated in 12 healthy male volunteers in a randomized, placebo-contro lled, cross-over design. The nasal spray was given in the morning, and subsequently blood and urine samples were collected for 26 hours. The re was a significant decrease in serum ionized calcium with a nadir 4 hours after administration of nasal SCT accompanied by a significant i ncrease in serum parathyroid hormone (P = 0.01) and serum calcitriol ( P = 0.04). Nasal SCT did not reduce urinary hydroxyproline/creatinine. Urinary deoxypyridinoline/creatinine was lowered significantly 2 hour s after administration of nasal SCT and throughout the first 24 hours, but remained unchanged for the last 2 hours. On a 24-hour basis, urin ary deoxypyridinoline/creatinine decreased from 14.1 (3.5) nmol/mmol t o 11.7 (3.2) nmol/mmol after nasal SCT (P = 0.04). Nasal SCT did not c hange the serum levels of alkaline phosphatase, osteocalcin, and the c arboxyterminal propeptide of type 1 procollagen. The results indicate that nasal SCT given as a single dose provokes a modest decrease in bo ne resorption lasting several hours, but leaves bone formation unaffec ted.