title: Effect of calcium supplementation on urinary hydroxyproline in osteoporotic postmenopausal women.
abstract: Although calcium supplements are widely used to reduce bone resorption in osteoporosis, their beneficial effect is not conclusively established. We studied the effect of a calcium supplement (1 g/day for 8 days) in 14 postmenopausal osteoporotic women. The fasting urinary hydroxyproline/creatinine ratio decreased from 0.022 +/- 0.001 to 0.017 +/- 0.001 (p less than 0.005) indicating a significant reduction in bone resorption. Both the tubular maximum for phosphate reabsorption (1.12 +/- 0.06 to 1.34 +/- 0.07, p less than 0.005) and plasma phosphate concentration (1.04 +/- 0.04 to 1.14 +/- 0.04, p less than 0.01) increased, consistent with suppression of parathyroid hormone activity. These results support the concept that calcium supplementation is useful in the treatment of postmenopausal osteoporosis.
mesh_terms: D000368:Aged; D001842:Bone and Bones / Q000378:metabolism; D002136:Calcium, Dietary / Q000008:administration & dosage*; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D006909:Hydroxyproline / Q000652:urine*; D008593:Menopause; D008875:Middle Aged; D010024:Osteoporosis / Q000188:drug therapy* / Q000652:urine; D010281:Parathyroid Hormone / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism
chemical_list: D002136:Calcium, Dietary; D010281:Parathyroid Hormone; D010710:Phosphates; D003404:Creatinine; D006909:Hydroxyproline