Effect of lithium on bone metabolism in organ culture.

The effects of lithium on bone metabolism were determined using different organ culture models for the study of resorption and collagen synthesis. At concentrations of 3 X 10(-3)--10(-2) M, lithium blocked the stimulation of 45Ca and lysosomal enzyme release by parathyroid hormone (PTH) but did not affect bone resorption in control cultures in the absence of PTH. Lithium inhibition was observed in continuous culture with PTH or when bones were exposed to both agents for only 8 h. Lithium was less effective in inhibiting resorption of bones pretreated with PTH, and pretreatment with lithium did not prevent subsequent stimulation of bone resorption by PTH. Lithium did not inhibit the incorporation of labeled proline in collagen and noncollagen protein or of labelled thymidine into DNA.