Identification of rat osteoclasts in bone smears with quantification of acid phosphatase activity in vitamin D deficiency.
Vitamin D deficiency may depress bone formation but its effect on bone resorption is not well defined. As an index of bone resorption, the activity of acid phosphatase, a lysosomal enzyme found in osteoclasts, was quantitated in situ from a bone tissue smear preparation. Activity of the enzyme, measured by integrative microdensitometry increased linearly from 25 to 60 min. The distribution of activity in osteoclasts quantitated appeared to follow a normal distribution with a median value of 0.19 integrated optical density units. Animals treated with vitamin D or 1,25 dihydroxycholecalciferol had significantly increased activity of acid phosphatase in osteoclasts compared to animals which were vitamin D deficient. The increase of acid phosphatase activity averaged 63%. Vitamin D or its metabolites may have a permissive effect on the action of parathyroid hormone or act directly to increase bone resorption.
Silverton
S F
SF
Department of Medicine, Montreal General Hospital, Quebec, Canada.
Kaye
M
M
D000135:Acid Phosphatase / Q000378:metabolism*; D000818:Animals; D001842:Bone and Bones / Q000033:anatomy & histology* / Q000201:enzymology; D005269:Femur / Q000201:enzymology; D010010:Osteoclasts / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D012886:Skull / Q000201:enzymology; D014808:Vitamin D Deficiency / Q000201:enzymology*
D000135:Acid Phosphatase