地塞米松对兔眼房水中一氧化氮及钙离子含量的影响

目的　观测兔眼球结膜下注射地塞米松后其眼压 (P)、房水流畅系数 (C)及房水中一氧化氮 (NO)浓度和Ca2 含量的变化 ,探讨NO、Ca2 在皮质类固醇性青光眼 (GIG)发病中的可能作用。方法　隔日定时给新西兰幼龄白兔双眼球结膜下注射地塞米松 0 5mg ,共 15次 ,3 0d ,隔日定时测定双眼眼压及C值 ,实验结束时抽取房水测定房水中NO及Ca2 浓度。结果　地塞米松使兔眼眼压升高 (P <0 0 5 )、C值及房水中NO浓度下降 (P <0 0 5 ) ;但对兔眼房水中Ca2 的含量无明显影响。结论　眼局部长期应用地塞米松可诱导高眼压 ,引起房水中NO含量显著降低 ,提示NO参与了GIG的发病

Effect of dexamethasone on NO and Ca2 + levels in rabbit aqueous humor

ObjectiveTo study the effect of dexamethasone on intraocular pressure(IOP),tonography,aqueous nitric oxide(NO) and Ca 2 levels in rabbit and investigate the possible role of NO and Ca 2 in glaucoma.Methods0.5 mg of dexamethasone was subconjunctivally injected bilaterally in 7 rabbits under general and topical anesthesia once every 2 days for 15 times.The changes of IOP,tonography,NO and Ca 2 levels in aqueous humor were observed and measured.ResultsTopical administration of dexamethasone significantly affected IOP,aqueous outflow facility and NO level in aqueous humor.Subconjunctival injection of dexamethasone caused a significant increase of IOP and decrease of aqueous outflow facility and NO level in comparison with control eyes (P<0.05),but Ca 2 level in aqueous humor was not obviously changed.ConclusionDexamethasone can induce glucocorticoid-induced-glaucoma (GIG).NO may be involved in the pathogenesis of GIG.