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- Satoh, Koichiro, et al.
(författare)
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Effect of methotrexate on fracture healing.
- 2011
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Ingår i: Fukushima journal of medical science. - : The Fukushima Society of Medical Science. - 0016-2590 .- 2185-4610. ; 57:1, s. 11-8
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Tidskriftsartikel (refereegranskat)abstract
- Low doses of methotrexate (MTX) are safe and effective for treating adult and juvenile rheumatoid arthritis. However, because this powerful anti-inflammatory drug might negatively influence the healing of wounds and fractures, MTX administration is often stopped during surgical procedures. The present study assesses the effects of low- and high-dose MTX on early inflammatory processes and bone healing in an experimental model of fracture. Thirty male Sprague-Dawley rats were assigned to low- and high-dose MTX and control groups. A femur was cut using a reciprocating saw and a 2-mm fracture gap was made using a fixator. One or four weeks thereafter, macrophages were immunostained and new bone formation was histomorphometrically measured. Significantly less new bone was formed in the high-dose MTX, than in the control group (p< 0.01), whereas bone formation did not significantly differ between the low-dose MTX and control groups. These results suggested that a low dose of MTX does not affect the early process of endochondral bone formation during fracture healing, whereas a high dose might delay the progress of new periosteal bone formation. Although more macrophages were found in the groups treated with MTX, their impact on surrounding inflammatory processes remains unclear.
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| 2. |
- Takahashi Sato, Kaoru, et al.
(författare)
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Local application of nucleus pulposus induces expression of P2X3 in rat dorsal root ganglion cells.
- 2012
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Ingår i: Fukushima journal of medical science. - 0016-2590. ; 58:1, s. 17-21
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Tidskriftsartikel (refereegranskat)abstract
- The P2X3 receptor is a ligand-gated cation channel that is activated by extra cellular adenosine triphosphate (ATP) found in the dorsal root, trigeminal and nodose ganglia. It is one of the receptors transmitting nociceptive information of injuries and inflammation of the periphery by endogenous ATP released from damaged cells. The present study was performed in order to evaluate if there was an increased expression of P2X3-immunoreactivity in dorsal root ganglion (DRG) neurons after experimental disc herniation. There were four groups: exposure of the left L4 dorsal root ganglion and incision of the L4-L5 disc, exposure and slight displacement of the left L4 dorsal ganglion, sham exposure of the L4 dorsal root ganglion, and normal. Seven days after surgery, the DRG's were collected, sectioned and stained immunohistochemically for the P2X3 receptor. The expression of P2X3 increased significantly following incision of the L4-5 disc compared to the normal group. Sham surgery induced a minor, although statistically significant increase. Mechanical displacement did not induce any increased expression of the receptors. The study demonstrates that expression of the P2X3 receptors in the DRG may be induced by local application of nucleus pulposus. This may increase our understanding of the pathophysiologic mechanisms related to disc herniation and sciatica.
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