Influence On Pituitary-adrenal Axis And Therapeutic Effect Of Methylprednisolone In Rats With Acute Pancreatitis

Objective: To observe acute pancreatitis(AP) how to influence on pathomorphology, hormone secretion, mediators of inflammation, and analyze relationships among endocrine, inflammatory system and hemodynamics. At the same time, to investigate methylprednisolone(MP) how effects on these factors, in order to explore its therapeutic effect and mechanism.Methods: We established models of acute edematous pancreatitis(AEP) and acute necrotizing pancreatitis(ANP) by retrograde injection sodium taurocholate(TCA) into biliopancreatic ducts in male SD rats. At 6 and 12 hours after induction, pathomorphology of pancreas, pituitary gland and adrenal gland under microscope and naked eyes was observed, else including ascites, concentration of interleukin 6(IL-6) , cortisol, adrenocorticotropic hormone(ACTH) and bete-endorphin(β-EP) in serum and cell apoptosis in pituitary gland and adrenal gland .Furthermore, we investigated MP how to effect those aspects in ANP.Results:1. Concentration of IL-6 rose(P<0.05 vs control group), but preserved stabilization in AEP(P>0.05 in 6h vs 12h).AEP did harm to pathology of pituitary gland and adrenal gland slightly, didn,t influence on both morphous and cell apoptosis(P>0.05 vs control group), and couldn,t confuse pituitary-adrenal axis and their hormone secretion. Concentration of cortisol rose in comparision with control group in 6h(P<0.05), but it degraded in 12h(P<0.05), the chang of their concentration was coincidence in cortisol and ACTH, and concentration ofβ-EP didn,t vary in comparision with control group(P>0.05).2. IL-6 rose remarkably and persistently in ANP(P<0.05 vs control group and AEP group,and P<0.05 in 6h vs 12h).ANP harmed adrenal gland and pituitary gland acutely, had influence obviously on both morphous and cell apoptosis(P<0.05 vs control group and AEP group), and confused pituitary-adrenal axis and hormone secretion. Concentration of cortisol decreased in comparision with AEP group in 6h(P<0.05) , the chang of their concentration was coincidence in cortisol and ACTH, and concentration ofβ-EP rose obviously in comparision with control group and AEP group(P<0.05).3. After MP interfered in ANP, the harm of pituitary, adrenal and pancreatic pathomorphology and inflammation lessened (pathomorphology score in pancreas under microscope and naked eyes: P<0.05 vs ANP group ), ascites score improved(P<0.05 vs ANP group) ,and concentration of IL-6(P<0.05 vs ANP group,and P<0.05 in 6h vs 12h) andβ-EP(P<0.05 vs ANP group,and P>0.05 in 6h vs 12h) degraded, but MP couldn,t improve the function of pituitary-adrenal axis and regulate hormone secretion. Concentration of cortisol rose remarkedly in 6h(P<0.05),but it degraded obviously in 12h(P<0.05), at the same time, the chang of their concentration was coincidence in cortisol and ACTH.Conclusions:1. The stabilization of endocrine system can maintain suitably steadiness of the disease in AEP. Because ANP destructs stabilization of the hypothalamic-pituitary-adrenal axis(HAP axis),the balance of feedback-negative feedback is confused in hormone secretion, which aggravated the disease.2. It is very important clinically to detect the concentration of IL-6 andβ-EP, which can predict the progression and grade in AP.3. MP can alleviate inflammation cascade reaction, disorder in hemodynamics and pancreatic inflammation, but the action time isn,t too long.4. MP can improve the pathomorphology in pituitary gland,adrenal gland and pancreas, but it can,t prevent the development of MODS in ANP.5. MP can,t adjust the disorder of the HPA axis.