Effects of calcitonin on transport and intracellular distribution of exchangeable Ca2+ in primary culture of bone cells.
The effects of calcitonin (CT) on the cellular transport and accumulation of Ca were studied in bone cells grown in primary culture. The following sequence of events was detected: (1) After 1--2 h of incubation with CT the initial rate of Ca influx into bone cells transiently increased. A longer incubation with CT (3--24 h), caused a gradual decrease in the initial rate of Ca influx, reaching a level below the control at 24 h. (2) After 2 h incubation with CT, efflux studies revealer Ca pool and (b) an increase in the accumulation of Ca in the slow-turnover Ca pool. (3) After 30 min of incubation with CT the amount of Ca in bone cells gradually increased and remained at a higher level for up to 24 h incubation with CT. It is suggested that the transient increase in the initial rate of Ca influx into bone cells, caused by CT, may provide the signal for the accumulation of Ca in the slow-turnover Ca pool, which is probably the mitochondria.
D000818:Animals; D001692:Biological Transport / Q000187:drug effects*; D001842:Bone and Bones / Q000378:metabolism*; D002116:Calcitonin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D051381:Rats
D002116:Calcitonin; D002118:Calcium