鼻息肉中诱导型一氧化氮合酶、Bax及Bcl-2的表达及相关性研究

目的:检测鼻息肉组织中诱导型一氧化氮合酶(iNOS)和凋亡相关基因Bax、Bcl-2的表达及相关性。方法:30例鼻息肉组织,应用TUNEL方法检测其凋亡情况;免疫组织化学SABC法检测iNOS及Bax、Bcl-2的表达;western blot方法检测iNOS、Bax、Bcl-2的表达。结果:①TUNEL方法检测凋亡细胞位于鼻息肉表层上皮细胞及腺体上皮细胞,均为弱阳性。②免疫组织化学法检测iNOS、Bax、Bcl-2均表达于鼻息肉组织上皮细胞、腺上皮细胞、血管内皮细胞和浸润的炎性细胞,阳性表达定位于细胞质,其中Bax表达为弱阳性,iNOS、Bcl-2表达为强阳性。③Western blot检测3种蛋白均有表达条带,iNOS、Bal-2条带清晰,Bax条带软弱,差异有统计学意义(P<0.01);iNOS与Bcl-2的灰度值比值呈正相关(r=0.851,P<0.01);iNOS与Bax的灰度值比值呈负相关(r=-0.714,P<0.01)。结论:鼻息肉组织中存在抗凋亡和促凋亡2种蛋白,iNOS抑制细胞凋亡,可能对鼻息肉的发生、发展起重要的促进作用。

The expression and correlation of inducible nitric oxide synthase, Bax and Bcl-2 in nasal polyps

Objective:To detect the expressions of inducible nitric oxide synthase(iNOS),apoptosis-related gene Bax,Bcl-2 in nasal polyps,and discuss the their relationship.Method:The apoptosis of 30 cases of nasal polyps was detected by TUNEL assay.The expressions of iNOS and Bax,Bcl-2 was detected by immunohistochemical SABC method.The expressions of iNOS and Bax,Bcl-2 was measured by western blot.Result:① The weakly positive stained apoptotic cells were detected at the surface epithelial cells and glandular epithelial cells of nasal polyps by TUNEL assay.②Immunohistochemical method revealed that positive stainings of iNOS,Bax,Bcl-2 located in the cytoplasm of epithelial cells,glandular epithelial cells,endothelial cells and infiltrating inflammatory cells in nasal polyps.The expression of Bax was weak,while the expressions of iNOS and Bcl-2 were strong.③iNOS,Bcl-2 and Bax was detected by western blot.The expressions of these proteins were significantly different(P<0.01).The expression of iNOS and Bcl-2 had a positive correlation(r=0.851,P<0.01),while the expression of iNOS and Bax had a negative correlation(r=-0.714,P<0.01).Conclusion:The pro-apoptotic and anti-apoptotic proteins are co-existed in the nasal polyps.iNOS may play an important role in the pathogenesy of nasal polyps through inhibition of apoptosis.