The Effect Of Glucocorticoid On Expression Of Transforming Growth Factor-β₁ Experimental Spinal Cord Injury In Rats

Objective: To investigate the effect of glucocorticoid(GC) on expression of transforming growth factor-p1(TGF- 1) after Spinal cord injury (SCI) in rats and the hole of TGF-pl plays in mechanism of GC deal with SCI. Methods: Make SCI model of rat to study the effect of GC to the expression of TGF-pl and TGF-plmRNA with immunohistochemical method and hybridization in situ.This study was devided into three parts.Part one: preparation of the SCI model of rat.85 adult SD rats were divided at random into 5 groupsigroup A without spinal cord injury ,group B with SCI using normal saline ,group C with SCI using small dose of DM,group D with SCI using high dose of DM, group E with SCI using high dose MP.Part two and part three:after operation the rats were sacrificed at 6h, 1 d, 3d, Td.The injured spinal cord tissue sections were stained with hematoxylin and eosin(HE), immunohistochemistry, RNA in situ hybridization.The effect of GC on expression of TGF-pl in SCI was evaluated.Results: the expression of TGF-pl and TGF-plmRNA is higher in the the injured spinal cord tissue than the spinal cord tissue without injured.Both small dose of DM and high dose MP could decrease the expression of TGF-pl and TGF-plmRNA and make the peak time of the expression ahead.But the high dose of DM might strengthen the expression of TGF-pl and TGF-pl mRNA.TGF-pl and TGF-p1 mRNA in rats with SCI received small dose of DM or high dose MP were significantly lower than that in the control.there was singificant differences between the group of high and small dose ofDM(P<0.01 or P<0.05),also between the groups of small dose of DM and highdose MP(P<0.01 or P<0.05).There was singificant differene between the groupsof high dose of DM and high dose MP(P<0.01 or P<0.05).Conclusion: MP and the small dose of DM may weak the protective effectsomehow on SCI by inhibiting the expression of TGF-j31.The high dose of DMmay increase the expression of TGF-J31 and TGF-pl mRNA.But themenchanism of the effect is not clear.The expression of TGF-pl was regulatedby GC on the mRNA level.