烫伤对大鼠下丘脑室旁核内皮素-1合成和分泌的影响

EFFECTS OF BURN ON SYNTHESIS AND SECRETION OF ENDOTHELIN 1 IN RAT PARAVENTRICULAR NUCLEUS OF HYPOTHALAMUS

目的 :研究烫伤后下丘脑室旁核 (PVH)内皮素 1(ET 1)的合成和分泌改变 ,探讨PVHET 1在烫伤中的病理生理学意义。方法 :用原位杂交和免疫组织化学方法观察了烫伤后PVHET 1合成和分泌的变化 ,并用通用图象颗粒分析法检测单位面积内ET 1mRNA阳性杂交信号的强度和ET 1样免疫反应物 (ET 1 ir)免疫反应强度。结果 :烫伤后 15minPVH神经元胞浆内ET 1mRNA阳性杂交信号与对照组相比未见明显差异 ,烫伤后 60min和 180minPVH神经元胞浆内ET 1mRNA阳性杂交信号较对照组 (10 0 %± 2 5 % )明显增多 ,强度明显增高 ,分别为 138%± 2 6% (P<0 .0 5 )和 167%± 18% (P <0 .0 1) ;而烫伤后 15minPVH神经元胞浆内ET 1阳性反应物明显减少 ,免疫反应物强度为 6.3%± 1.5 % ,显著低于对照组 (P <0 .0 1) ,烫伤后 60min和 180min逐渐回升 ,分别为 2 3.1%± 2 .9%和44 .1%± 3.8% ,但仍显著低于对照组 (P <0 .0 1)。结论 :烫伤后PVHET

Aim and Methods: In order to investigate the pathophysiological role of ET 1 in paraventricular nucleus of hypothalamus (PVH) under burn, changes in synthesis and secretion of endothelin 1 (ET 1) in PVH after burn were observed by in situ hybridization and immunohistochemistry. The intensity of ET 1 mRNA and ET 1 immunoreactivity (ET 1 ir) were quantized by image analysis. Results: Compared with the control group (sham burn,100%±25%), no significant change in the intensity of ET 1 mRNA positive hybridization signal in PVH was found at 15 min postburn, while the intensity increased significantly both at 60 min (138%±26%, P <0.05) and at 180 min postburn (167%±18%, P <0.01). Intensity of ET 1 ir in the neurons in PVH decreased significantly at 15 min postburn to 6.3%±1.5% of the control ( P <0.01) and gradually recovered to 23.1%±2.9% and to 44.1%±3.8% at 60 min and 180 min postburn respectively, while still significantly lower than that in control( P <0.01). Conclusion: The results demonstrated that the synthesis and secretion of ET 1 in rat PVH increased significantly after burn in rats, suggesting that ET 1 in PVH played an important pathophysiological role under burn.