The effects of high-dose glucocorticoid administration on serum bone gamma carboxyglutamic acid-containing protein, serum alkaline phosphatase and vitamin D metabolites in normal subjects.
The effects of 40 mg of prednisone given daily for 5 days to normal individuals on serum levels of bone Gla-protein (BGP), alkaline phosphatase, calcium phosphate, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D and immunoreactive parathyroid hormone (S-iPTH) and on renal excretions of calcium, phosphate and hydroxyproline were evaluated in a double-blind, placebo controlled study. In the prednisone group a 75% decrease (P less than 0.001) was found in serum BGP compared to a 6% decrease (P less than 0.05) in serum alkaline phosphatase. The renal hydroxyproline excretion remained unchanged. Serum calcium was unchanged while the fasting urinary calcium excretion showed a 2-fold increase (P less than 0.001). Serum 1,25-dihydroxyvitamin D increased (P less than 0.01) in spite of unchanged serum 25-hydroxyvitamin D, serum phosphate and parathyroid function (as judged by S-iPTH and the maximal tubular reabsorption capacity for phosphate (TmP/GFR]. The data suggest a direct inhibition of osteoblast number and/or function by short-term glucocorticoid administration with unchanged bone resorption leading to a negative bone mineral balance. The increase in serum 1,25-dihydroxyvitamin D is probably due to a direct stimulation by glucocorticoids of the renal 1 alpha-hydroxylase. The effects of the vitamin D metabolite, however seem to be blunted.
Nielsen
H K
HK
Medical Department III, Arhus Amtssygehus, Denmark.
Thomsen
K
K
Eriksen
E F
EF
Charles
P
P
Storm
T
T
Mosekilde
L
L
D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood*; D001842:Bone and Bones / Q000502:physiology*; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002130:Calcium Phosphates / Q000097:blood; D002135:Calcium-Binding Proteins / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006801:Humans; D006909:Hydroxyproline / Q000652:urine; D008297:Male; D015675:Osteocalcin; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood / Q000652:urine; D011241:Prednisone / Q000494:pharmacology*; D014807:Vitamin D / Q000097:blood*
D002130:Calcium Phosphates; D002135:Calcium-Binding Proteins; D010281:Parathyroid Hormone; D010710:Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D015675:Osteocalcin; D014807:Vitamin D; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; D000469:Alkaline Phosphatase; D002117:Calcitriol; C485829:calcium phosphate, dibasic, anhydrous; D002112:Calcifediol; D006909:Hydroxyproline; D011241:Prednisone