目的探讨糖皮质激素受体(GR)α和β mRNA在甲状腺相关眼病(TAO)患者眼眶组织中的表达。方法眼外肌和(或)眼眶脂肪组织标本取自在我科行手术治疗的17例严重TAO患者,意外死亡的10例健康成年人眼外肌和(或)眼眶脂肪组织标本作为对照。提取眼外肌或眶脂肪组织总RNA,将RNA逆转录为cDNA,用荧光定量聚合酶链反应(PCR)方法实时检测GRα和GRIβ的PCR扩增全过程,计算各个样本GRα和GRIβ mRNA的表达量。结果眼外肌和眶脂肪组织均表达GRα和GRβ mRNA。TAO患者GRα mRNA表达量为(40.15±11.37)拷贝/μ1,正常对照为(20.64±7.07)拷贝/μl。TAO患者GRα mRNA表达量与GRβ mRNA表达量的比值(GRα/GRβ比值)为77.76±18.77,正常对照为148.34±23.86,差异具有统计学意义(P<0.05)。眼外肌与眶脂肪组织之间,甲状腺机能正常、亢进及低下患者之间,使用糖皮质激素治疗与未使用糖皮质激素患者之间GRα mRNA表达量和GRα/GRβ比值比较,差异均无统计学意义(P>0.05)。结论TAO患者眼眶组织GRα mRNA的表达增强;GRα/GRβ比值降低可能在TAO的病理发生和糖皮质激素的治疗反应中起一定作用。
Objective To evaluate the expression of glucocorticoid receptor alpha (GRα)and beta (GRβ) messenger RNA (mRNA) in orbital tissues from thyroid associated ophthalmopathy (TAO). Methods Samples of extraocular muscle and orbital fat were obtained from 17 patients with TAO and 10 healthy individuals. Total RNA was extracted and reversely transcfipted into cDNA. The expression of GRα and GRβ mRNA was detected by means of fluorescent quantitative polymerase chain reaction (PCR). Results Expression of GRα mRNA was much higher than GRβ mRNA in all extraocular muscle and orbital fat biopsies. The relative copy of GRα was 40.15 ±11.37 in TAO patients and 20.64±7.07 in the controls. GRα: GRβ mRNA ratio of these two groups was 77.76 ± 18.77 and 148.34 ± 23.86, respectively. There was significant difference between these two groups ( P 〈 0.05 ). No significant difference was noted between extraocular muscle and orbital fat biopsies, between glucocorticoid-treated and non-treated patients or among hyperthyroidism, hypothyroidism and euthyroidism ( P 〉 0. 05 ). Conclusions The increased expression of GRα mRNA and decreased GRα: GRβ ratio in orbital tissues may play an important role in the pathogenesis of TAO and the effects of glucocorticoid treatment.