臨床および実験薬理学ジャーナル

概要

Effect of Teripratide and Alendronate on Spinal Fusion in Rats with Glucocorticoid: Induced Osteoporosis

Mohamed El-Sayed Mahmoud

Background: Spinal fusion surgery is one of the standard treatments for degenerative and traumatic spine diseases, delayed union or pseudarthrosis of grafting bone after surgery create more serious problems in performing spinal fusion surgery for patients with Glucocorticoid Induced Osteoporosis (GIOP). Purpose: To elucidate the effect of intermittent administration of TPTD or alendronate on spinal fusion in rats with GIOP. Study design: An experimental animal study of rats under continuous glucocorticoid (GC) exposure undergoing spinal fusion surgery and administration of TPTD or Alindronate. Methods: 24 Male albino rats weighing 250-300 g. Six rats were subcutaneously injected with saline per week for 6 weeks before. The other 18 rats were subcutaneously injected with MP five times per week at a dose of 5 mg/kg/d for 6 weeks before surgery. After 6 weeks of MP administration, rats were randomized into three groups before surgery; rats in the control group (CNT group; n6) were given subcutaneous injections of 0.9% saline five times per week for 6 weeks, and rats in the alendronate group (n6) were given subcutaneous injections of 15 mcg/kg/d of alendronate for 6 weeks and rats in the TPTD group (n6) were given subcutaneous injections of 40 mcg/kg/d of TPTD five times per week for 6 weeks. After grouping, all rats were underwent posterolateral spinal fusion (L4–L5) with iliac crest autograft. The following assessments were performed: microstructural analysis of the fusion mass and adjacent vertebrae (L6); fusion assessment, with manual palpation testing; and bone histomorphometrical analysis of the fusion mass. Results: in the alendronate group and In the TPTD group, values for bone volume and other bone microstructural parameters at the fusion mass increased and peaked 4 weeks after surgery, and these values were significantly greater than those for the control (CNT) group at 4 and 6 weeks after surgery. Fusion assessment showed that fusion rate was higher in the alendronate group and in the TPTD group than in the CNT group (CNT group: 0%, alendronate group 67%; TPTD group: 84%). Conclusion: Under continuous GC exposure in a rat model of spinal fusion, alendronate or intermittent TPTD administration were stimulating bone formation at the fusion mass and increasing the fusion rate. Intermittent TPTD administration also improved bone microarchitecture of adjacent vertebrae