三步序贯法对激素干预后哮喘大鼠模型HPA轴功能的影响

目的：观察三步序贯法对激素干预后哮喘大鼠模型HPA轴功能的影响。方法：将SD大鼠随机分为正常对照组、哮喘模型组、激素干预组、三步序贯组、第一步方组、第二步方组、第三步方组、普米克令舒组。制备激素干预后哮喘大鼠模型，于第3周起开始撤减激素用量，按照每周地塞米松0．1mg／kg速度递减，直至第7周完全撤除。放免法检测各组大鼠不同时段血浆促肾上腺皮质激素释放激素（CRH）、促肾上腺皮质激素（ACTH）和皮质酮（COR）含量的变化。结果：与哮喘模型组比较，经过激素（地塞米松）长期干预后，激素干预组、第一、二、三步方组以及普米克令舒组在第7、9周末，其血浆CRH、ACTH和COR含量呈普遍下降，其中尤以激素干预组下降最为显著（P均〈0．01）。与激素干预组比较，三步序贯组在第7、9周末其血浆CRH、ACTH和COR含量明显升高（P〈0．05，P〈0．01），与哮喘模型组比较，二者之间均无显著性差异（P均〉0．05）。结论：三步序贯法对激素干预后哮喘大鼠模型HPA轴功能具有明显的恢复作用。

Effect of Three-stage Sequential Method on Hypothalamic-Pituitary-Adrenal Axis in Asthmatic Rat Models after Steroid Intervention

Objective: To observe the effect of three-stage sequential method on the hypothalamic-pituitary-adrenal axis in asthmatic rat models after steroid intervention.Methods: SD rats were randomly divided into eight groups,the control group(CG),the asthmatic group(AG),the steroid intervention group(SIG),the three-stage sequential group(TSSG),the first stage group(FSG),the second stage group(SSG),the third stage group(TSG) and the Pulmicort Respules group(PRG).The asthmatic rat model with steroid intervention was established.Dexamethasone began to be withdrawn from the third week at a speed of 0.1mg per kilogram and was completely withdrawn till the 7th week.The plasma concentrations of CRH,ACTH and COR of different groups were determined by radioimmunoassay.Results: Compared with the AG,the plasma concentrations of CRH,ACTH and COR in the SIG,FSG,SSG,TSG and PRG were all reduced at the 7th and 9th weekend after the long intervention of steroid,especially in the SIG.Compared with the SIG,the plasma concentrations of CRH,ACTH and COR in the TSSG were increased significantly and no difference was found between the TSSG and the AG at the 7th and 9th weekend(P>0.05).Conclusion: Three-stage sequential method could recover the functions of HPA axis of asthmatic rat models with steroid intervention.