Effects of ovariectomy and tamoxifen on rat bone tissue: histomorphometric and histopathologic study.
OBJECTIVE
To investigate possible detrimental effects on bone tissue induced by ovariectomy and tamoxifen (TMX) using bone densitometry and histomorphologic analysis.


METHODS
Twenty-four rats were allocated into 4 groups: group 1, intact normal rats (n = 6); group 2, ovariectomized rats (n = 6); group 3, normal female rats that received 1 mg/kg/day TMX dissolved in dimethyl sulfoxide (DMSO) for 2 months (n = 6); group 4, normal female rats that received DMSO for the same duration and with a volume equal to that of TMX (n = 6). Results of histomorphometric analysis for trabecular thickness, number of osteoblasts and osteoclasts, trabecular number, and area and cortical thickness were compared.


RESULTS
No significant effects of ovariectomy on femoral or lumbar bone mineral density (BMD) were found. In the TMX group, the value of femoral BMD increased significantly compared to control group cellular and pathologic changes. TMX caused significant decrease in osteoblasts compared to the control group.


CONCLUSIONS
TMX has a positive effect on inorganic bone tissue, but a negative effect on number of osteoblasts and osteoclasts. Future studies investigating estrogenic and antiestrogenic effects of TMX should include cellular parameters related to proliferation using histopathologic and histomorphometric analyses.
Aktug
Hüseyin
H
Department of Histology and Embryology, Ege University School of Medicine, Izmir, Turkey. haktug35@yahoo.com.tr
Uslu
Serap
S
Terek
Mustafa Coşan
MC
Terzi
Hasan
H
Turgut
Mehmet
M
Ozşener
Serdar
S
Bilgin
Onur
O
D000818:Animals; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000737:chemistry / Q000187:drug effects* / Q000473:pathology*; D005260:Female; D005269:Femur / Q000737:chemistry / Q000187:drug effects / Q000473:pathology; D008159:Lumbar Vertebrae / Q000737:chemistry / Q000187:drug effects / Q000473:pathology; D010012:Osteogenesis / Q000187:drug effects; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013629:Tamoxifen / Q000494:pharmacology*
D013629:Tamoxifen