内源性一氧化碳对变应性鼻炎豚鼠诱导型一氧化氮合酶表达的影响

目的 制备豚鼠变应性鼻炎(allergic rhinitis,AR)动物模型,研究在AR豚鼠模型中内源性一氧化碳(carbon monoxide,CO)对诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)表达的影响.方法 24只豚鼠以随机数字表法分为4组,每组6只.第1组以生理盐水处理作为正常对照组,第2(AR组)、3、4组以卵清蛋白(ovalbumin,OVA)致敏,制成AR动物模型,第3、4组再分别以血红素氧合酶1(hemeoxygenase 1,HO-1)诱导剂氯化血红素和抑制剂锌原卟啉干预处理,分别作为HO诱导组和HO抑制组,分别测定各组豚鼠血浆中碳氧血红蛋白(carboxyhemoglobin,COHb)的百分含量(用来代表血浆中CO含量),并采用实时荧光定量反转录聚合酶链反应(RT-PCR)法测定鼻黏膜中HO-1和iNOS的相对表达量.结果 第2、3、4组豚鼠AR造模成功.血浆COHb含量(x-±s,以下同)第2组(2.27%±1.13%)高于第1组(1.08%±0.24%),差异有统计学意义(q=4.10,P＜0.01);第3组(3.17%±0.68%)高于第2组,差异有统计学意义(q=3.12,P＜0.05).鼻黏膜中HO-1、iNOS的相对表达量(x-±s,以下同)第2组[分别为(7.80±1.60)×10~(-3)和(5.81±0.05)×10~(-3)]高于第1组[分别为(1.96±0.71)×10~(-3)和(0.97±0.05)×10~(-3)],差异有统计学意义(q值分别为5.52、7.21,P值均＜0.01),第3组[分别为(11.89±4.78)×10~(-3)和(7.42±0.70)×10~(-3)]高于第2组,差异有统计学意义(q值分别为3.86、2.22,P值均＜0.05),第4组[分别为(3.82±0.98)×10~(-3)和(2.34±0.04)×10~(-3)]低于第2组,差异有统计学意义(q值分别为3.76、5.18,P值均＜0.05).结论 内源性CO在AR中影响iNOS的表达.

Influence of carbon monoxide on the expression of inducible nitric oxide synthase mRNA in guinea pigs with allergic rhinitis

Objective To study the impact of carbon monoxide(CO)on expression levels of inducible nitric oxide synthase(iNOS)mRNA in guinea pigs with allergic rhinitis(AR).Methods Twenty four guinea pigs were divided randomly into four study groups with 6 guinea pigs in each.The guinea pigs in the first group were treated with saline only(Group 1,the healthy controls).The remaing guinea pigs were sensitized by ovalbumin and thus establishing the AR models.After sensitization,the animals in the second group remained untreated(Group 2,AR control group).The third group was treated with Hemin as the induction group,and the fourth group was treated with Zinc protoporphyrin(ZnPP)as the suppression group.The plasma concentration of carboxyhemoglobin(COHb)was measured,which represents the concentration of CO.The expression levels of Heme oxygenase-1(HO-1)and NOS mRNAs in nasal mucosa were determined by fluorescent quantitative RT-PCR.Results AR models were established successfully in all study guinea pigs.The concentrations of COHb(x-±s)in plasma of the second group(2.27% ±1.13%)were significantly(q=4.10,P＜0.01)higher than those of healthy controls(1.08% ± 0.24%).The plasma concentration of COHb in the third group(3.17% ±0.68%)were also significantly higher(q=3.12,P＜0.05)than those in the second group.The expression levels of HO-1 and iNOS in nasal mucosa of the second group[(7.80 ± 1.60)×10~(-3) and(5.81 ±0.05)×10~(-3),respectively]were also significantly(q equals 5.52 and 7.21,respectively,P＜0.01)higher than those of controls[(1.96 ±0.71)×10~(-3) and(0.97 ±]0.05)×10~(-3),respectively].The expression levels of HO-1 and iNOS in the nasal mucosa of the third group[(11.89 ± 4.78)×10~(-3) and(7.42 ± 0.70)×10~(-3),respectively]were significantly(q equals 3.86 and 2.22,P＜0.05)higher than those of the second group.The expression levels of HO-1 and iNOS in nasal mucosa of the fourth group[(3.82 ±0.98)×10~(-3) and(2.34 ±0.04)×10~(-3),respectively]were significantly(q equals 3.76 and 5.18,P＜0.05)lower than those in the second group.Conclusions Endogenous carbon monoxide influenced the expression levels of iNOS in nasal mocusa in guinea pigs with AR.