HYDROCHLOROTHIAZIDE INHIBITS PARATHORMONE-STIMULATED INCREASE IN PLASMA TARTRATE-RESISTANT ACID-PHOSPHATASE IN MICE

The inhibitory effect of hydrochlorothiazide (HTZ) on parathormone-induced bone changes in mice was studied with the aid of the analysis of plasma calcium and tartrate-resistant acid phosphatase. We have found that HTZ alone had no effect on plasma tartrate-resistant acid phosphatase (Tr-ACP), phosphate, and creatinine concentration. Parathormone (PTH) administration increased plasma Tr-ACP from 15.00 +/- 1.50 to 20.62 +/- 2.35 U/liter in intact mice. The increase of plasma Tr-ACP in HTZ-treated mice after PTH administration was not significant. The plasma calcium was affected in a way similar to Tr-ACP. HTZ reduced the sensitivity of bone to resorbing effects of PTH, using Tr-ACP as a useful biomarker of bone resorption.