Interaction of androgen and 1,25-dihydroxyvitamin D3: effects on normal rat bone cells.
We studied the actions of testosterone (T) and 5 alpha-dihydrotestosterone (DHT) in combination with 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] on primary rat bone cells. The actions of androgens were generally anabolic, although response patterns varied considerably between cultures. For example, DHT caused striking dose- and time-dependent increases in [3H]thymidine incorporation into calvarial cells over the range 1-100 nM, with maximal stimulation of 2.5-fold after 9 days in culture. Testosterone (50 nM) also stimulated [3H]thymidine incorporation into long bone-derived cells. 1,25-(OH)2D3 generally blunted or abolished the proliferative action of androgens but was not itself always inhibitory; in some experiments, stimulation of [3H]thymidine incorporation occurred. Collagen production, as assessed by [3H]proline incorporation into pepsin-resistant protein secreted by calvarial cells, was also stimulated by DHT. In some cultures, androgen responses were absent, although striking inhibitory responses to 1,25-(OH)2D3 were observed. These results illustrate complex patterns of responses to androgens and 1,25-(OH)2D3 in cells derived from rat bone.
Gray
C
C
Department of Anatomy and Developmental Biology, University College London.
Colston
K W
KW
Mackay
A G
AG
Taylor
M L
ML
Arnett
T R
TR
D000469:Alkaline Phosphatase / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001842:Bone and Bones / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002117:Calcitriol / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis; D013196:Dihydrotestosterone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000494:pharmacology*
D013196:Dihydrotestosterone; D013739:Testosterone; D003094:Collagen; D000469:Alkaline Phosphatase; D002117:Calcitriol