Abstract | BACKGROUND: Although the role of the osteoclast in bone resorption is becoming better understood, much remains to be learned about osteoclastogenesis and the exact mechanism of action of anti-resorbing agents such as 17beta-estradiol. This study investigated bone and morphologic osteoclast alterations following long-term estrogen administration to the B6D2F1 mouse. B6D2F1 mice aged 4-5 weeks were exposed to high levels of estrogen via implanted silastic tubing for at least 12 weeks; controls received empty tubing. Femurs of control and treated mice were assessed with radiology, quantitative histomorphometry and transmission electron microscopy. RESULTS: After 8 weeks of treatment, there was radiologic evidence of severe osteosclerosis and 86% of femoral marrow space was replaced with bone. After 12 weeks histologic studies of treated animals revealed that osteoclasts were positive for tartrate-resistant acid phosphatase but showed markedly abnormal ultrastructure which prevented successful bone resorption. CONCLUSIONS: Findings extend our understanding of osteoclast structure and function in the mouse exposed in vivo to high doses of estrogen. Ultrastructural examination showed that osteoclasts from estrogen-treated mice were unable to seal against the bone surface and were unable to form ruffled borders.
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Authors | H E Gruber, I J Puzanov, M Bennett, V Kumar, B Gordon |
Journal | BMC cell biology
(BMC Cell Biol)
Vol. 2
Pg. 3
( 2001)
ISSN: 1471-2121 [Electronic] England |
PMID | 11231877
(Publication Type: Journal Article)
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Chemical References |
- Isoenzymes
- Estradiol
- Acid Phosphatase
- Tartrate-Resistant Acid Phosphatase
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Topics |
- Acid Phosphatase
(analysis)
- Animals
- Estradiol
(pharmacology)
- Femur
(anatomy & histology, diagnostic imaging, ultrastructure)
- Isoenzymes
(analysis)
- Kinetics
- Mice
- Osteoclasts
(drug effects, enzymology, ultrastructure)
- Radiography
- Tartrate-Resistant Acid Phosphatase
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