Pharmacological treatment of osteopenia induced by gastrectomy or ovariectomy in young female rats.
BACKGROUND
Both gastrectomy (GX) and ovariectomy (OVX) induce osteopenia in man and experimental animals. The present study addresses the question--can alendronate, estrogen or parathyroid hormone (PTH) be used to treat established GX- or OVX -evoked osteopenia?


METHODS
Rats were GX-, OVX- or SHAM-operated 8 weeks before starting the treatment with drugs. Each group was then treated for 8 weeks with 50 microg/kg/day alendronate, 10 microg/kg/day estrogen or 75 microg/kg/day PTH(1-84); n = 8 rats/group. Peripheral Quantitative Computed Tomography (pQCT) was used to measure trabecular bone mineral density (BMD) and various cortical bone parameters.


RESULTS
At killing, 16 weeks after surgery, GX and OVX rats had a greatly reduced trabecular BMD in the metaphysis of the distal femur (GX -44% and OVX -55%). Alendronate increased the trabecular BMD by 44% in GX rats and by 64% in OVX rats, while PTH increased it by 51% and 115%, respectively. However, estrogen increased the trabecular BMD in GX rats (35%), but not in OVX rats (15%, not significant). Cortical bone parameters were adversely (but moderately) affected by GX, but not by OVX or by treatment with the three drugs.


CONCLUSIONS
Alendronate, estrogen and PTH restored the trabecular bone loss in rats with an established GX-evoked osteopenia. In contrast, alendronate and PTH, but not estrogen, restored the trabecular bone loss after OVX. Hence, the mechanism underlying GX-evoked bone loss differs from that underlying OVX-evoked bone loss. The ability of alendronate, estrogen and PTH to reverse the GX-evoked osteopenia in the rat may be of clinical interest when dealing with bone loss in humans after GX.
Andersson
Niklas
N
Department of Pharmacology, Institute of Physiological Sciences, Lund University, BMC F-13, SE-221 84 Lund.
Surve
Vikas V
VV
Lehto-Axtelius
Daisy
D
Andersson
Kjell
K
Ryberg
Birgitta
B
Ohlsson
Claes
C
Håkanson
Rolf
R
D019386:Alendronate / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D015519:Bone Density / Q000187:drug effects / Q000502:physiology; D001851:Bone Diseases, Metabolic / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D004164:Diphosphonates / Q000494:pharmacology / Q000627:therapeutic use*; D004967:Estrogens / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D005743:Gastrectomy / Q000009:adverse effects*; D006728:Hormones / Q000494:pharmacology / Q000627:therapeutic use*; D023421:Models, Animal; D010052:Ovariectomy / Q000009:adverse effects*; D010281:Parathyroid Hormone / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D014057:Tomography, X-Ray Computed
D004164:Diphosphonates; D004967:Estrogens; D006728:Hormones; D010281:Parathyroid Hormone; D019386:Alendronate