Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0205700 (ash)
 15,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of the present study was to examine the effect of therapeutic doses of glucocorticoids on the mechanical strength of rat femora. Groups of rats were treated with a glucocorticoid--methylprednisolone (Solu-Medrol)--1 mg/kg/day for 5, 10, 30, and 90 days. One group served as intact control, two control groups were injected with saline for 30 and 90 days and another group of rats had restricted access to food so that their weight gain was reduced to the same extent as the group treated with glucocorticoid for 90 days. The strength of the femora was analyzed by means of a materials testing machine. No differences were found in the short-term treated groups compared to the control groups, but in the group treated with glucocorticoid for 90 days, a reduction in the bending strength of the rat cortical bone was found. Furthermore, this reduction in strength was found after correction for the reduced thickness of cortical bone in the glucocorticoid-treated rats. The results could not be explained solely by the fact that glucocorticoid-treated rats had smaller bones. No alterations were found in bone density or bone ash weight relative to dry weight. The data indicate that the reduction in bone strength induced by glucocorticoids is not only caused by a reduction in bone quantity, but also by a decrease in bone quality.
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PMID:Reduced strength of rat cortical bone after glucocorticoid treatment. 314 27

Longitudinal bone mineral measurement was performed by dual X-ray absorptiometry (DXA) in fifty 14-week-old Wistar rats divided into the following five groups: ovariectomized (OVX); sham-ovariectomized (SHAM); ovariectomized with release of proximal tail muscles (OVX + MR); prednisolone-administered (PDN); and saline-administered (control). Bone mineral density (BMD) was measured at the skull, distal femur, proximal tibia, and caudal vertebrae at 4, 8, 12, 16, 20, and 24 weeks after surgery or onset of administration. This in vivo DXA technique accurately showed correlation with the ash weight (r = 0.912-0.971), with a precision error of 1.01-2.05%. In the OVX group, the percent changes in distal femoral BMD and proximal tibial BMD were -7.6% and -5.3% at four weeks, followed by a gradual increase toward the initial value by 12 weeks. On the other hand, both OVX and SHAM rats gained BMD of the skull and caudal vertebrae. OVX+MR rats also gained BMD of the caudal vertebrae. Release of proximal tail muscles only had no significant effect on bone mineral of the caudal vertebrae. Prednisolone had no significant effect on bone mineral at any site.
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PMID:Longitudinal study of in vivo bone mineral changes in rats using dual X-ray absorptiometry--effect of ovariectomy and prednisolone. 830 12