Effects of salmon calcitonin on synthesis and mineralization of collagen in rats.

The effects of salmon calcitonin (CT) on collagen metabolism and mineral deposition in fractures and intact femora, and on collagen metabolism in healing skin wounds and intact skin have been studied in young male rats. Serum calcium and serum phosphorus were reduced 3 h after the daily subcutaneous CT injection (3 MRC-U/kg body weight), whereas a rebound increase in the serum levels of both minerals was observed at 24 hours after the injection. CT had an early transient inhibitory influence on the collagen synthesis, and this resulted in a reduced total content of collagen in bones and skin specimens from treated rats compared to controls. The concentration of collagen in bone and skin was, however, increased in treated animals compared to controls after prolonged CT administration. Following an early transient increase, the incorporation of strontium-85 into the fractured bones was impaired after 30 days of CT treatment. This resulted in a reduced mineral concentration in the fractures of treated rats compared to controls in the last part of the experiment. The recorded effects of CT treatment, which were most pronounced in healing fractures and intact skin specimens, may be interpreted as an inhibitory influence of CT both on synthesis, mineralization and degradation of collagen.