Effects of heterocyclic sulfonamides on bone metabolism

Sulfonamide inhibitors of carbonic anhydrase attenuate parathyroid hormone and vitamin D3 induced bone resorption. Parathyroid hormone stimulates bone cell accumulation of cAMP in the presence of concentrations (10(-7) - 10(-3) M) of acetazolamide (an inhibitor of carbonic anhydrase) that are antagonistic to bone resorption. Bone cell acid phosphatase activity and lactic acid production are stimulated by parathyroid hormone or vitamin D3. These cellular responses are not influenced by the presence of acetazolamide (10(-4) M). Bone cells incubated in the presence of parathyroid hormone reveal an increase in carbonic anhydrase like activity. This activity is lost upon heating a supernatant of the bone cell population or upon treatment of the supernatant with appropriate concentrations of acetazolamide.