Ultrastructural-immunocytochemical localization of endogenous calcitonin in osteoblasts of silicon-treated rats.
Immunoreactivity to endogenous calcitonin was studied in osteoblasts from calvaria of neonatal rats, by immunocytochemistry with the use of ultrathin sections obtained by cryoultramicrotomy. The influence of a silicon-treatment on the localization of endogenous calcitonin in osteoblasts of rats, was tested. Endogenous calcitonin-like immunoreactivity was observed in osteoblasts of calvaria of control and of silicon-treated rats, and showed a similar subcellular localization in both types of rats. Calcitonin was observed at the plasma membrane level, in the cytoplasmic matrix, and in the nucleus. The results provide immunocytological evidence for: 1) the internalization of calcitonin in osteoblasts of rat calvaria; 2) a similar localization of calcitonin in osteoblasts of control or silicon-treated rats.
Boivin
G
G
INSERM Unité 234, Faculté Alexis Carrel, Lyon.
Morel
G
G
Charnot
Y
Y
Meunier
P J
PJ
Dubois
P M
PM
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002116:Calcitonin / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D007124:Immunoenzyme Techniques; D008297:Male; D008854:Microscopy, Electron; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D012825:Silicon / Q000494:pharmacology*
D002116:Calcitonin; D012825:Silicon