Effects of parathyroid hormone and calcitonin on alkaline phosphatase activity and matrix calcification in rabbit growth-plate chondrocyte cultures.
The effects of PTH and calcitonin (CT) on the expression of mineralization-related phenotypes by chondrocytes were examined. In cultures of pelleted growth-plate chondrocytes. PTH caused 60-90% decreases in alkaline phosphatase activity, the incorporation of 45Ca into insoluble material, and the calcium content during the post-mitotic stage. These effects of PTH were dose-dependent and reversible. In contrast, CT increased alkaline phosphatase activity, 45Ca incorporation into insoluble material, and the calcium content by 1.4- to 1.8-fold. These observations suggest that PTH directly inhibits the expression of the mineralization-related phenotypes by growth-plate chondrocytes, and that CT has the opposite effects.
Kato
Y
Y
Department of Biochemistry, Faculty of Dentistry, Osaka University, Japan.
Shimazu
A
A
Nakashima
K
K
Suzuki
F
F
Jikko
A
A
Iwamoto
M
M
D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D002113:Calcification, Physiologic / Q000187:drug effects*; D002116:Calcitonin / Q000494:pharmacology*; D002132:Calcium Radioisotopes / Q000378:metabolism; D002478:Cells, Cultured; D004247:DNA / Q000378:metabolism; D005109:Extracellular Matrix / Q000378:metabolism*; D006132:Growth Plate / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010281:Parathyroid Hormone / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology; D011817:Rabbits
D002132:Calcium Radioisotopes; D010281:Parathyroid Hormone; D010446:Peptide Fragments; C025076:parathyroid hormone (1-34), bovine; D002116:Calcitonin; D004247:DNA; D000469:Alkaline Phosphatase