【摘要】 旨在比较牦牛和柴达木黄牛低氧通气反应(HVR)特征及颈动脉体(CB)中一氧化氮(NO)、一氧化氮合酶(NOS)含量。选择生活在海拔3 200m临床健康的成年牦牛和柴达木黄牛进行13.9%O2低氧(模拟海拔6 000m)通气反应;采用荧光定量PCR、酶联免疫吸附(ELISA)双抗体夹心法和免疫组织化学方法对海拔3 200m牦牛、柴达木黄牛及模拟海拔6 000m时CB中的NOS mRNA和蛋白水平表达以及NO含量进行检测。结果表明:牦牛、柴达木黄牛低氧通气反应斜率(△VE/△SaO2)分别为(0.21±0.10)和(0.50±0.21)(L·min-1)/%SaO2(P<0.01);海拔3 200m时,CB中nNOS、eNOS、iNOS基因mRNA和蛋白表达水平在牦牛与柴达木黄牛间差异均不显著(P>0.05),模拟海拔6 000m时,CB中nNOS、eNOS、iNOS蛋白表达水平在牦牛与柴达木黄牛间差异均不显著(P>0.05),模拟海拔6 000m的牦牛、柴达木黄牛CB中nNOS、eNOS、iNOS蛋白表达水平分别与海拔3 200m的牦牛、柴达木黄牛比较差异均不显著(P>0.05);在模拟海拔6 000m组,牦牛、柴达木黄牛CB中NO含量均显著高于海拔3 200m(P<0.01或P<0.05),在模拟海拔6 000m组,牦牛CB中NO含量极显著高于柴达木黄牛(P<0.01),在海拔3 200m,牦牛与柴达木黄牛CB中NO含量差异不显著(P>0.05)。结果提示,青藏高原世居牦牛低氧通气反应钝化,而柴达木黄牛对低氧的刺激保持较高的通气反应,急性低氧时牦牛CB内产生大量的NO可抑制对低氧的化学感受。更多还原

【Abstract】 The aim of the present study to compare the hypoxic ventilatory response(HVR)characteristic and the content of nitric oxide(NO),nitric oxide synthase(NOS)in carotid body(CB)between yaks and Qaidam yellow cattle.In this study,health adult yaks and Qaidam yellow cattle at altitude of 3 200 mwere inhaled hypoxic gas of 13.9% O2,which was simulated to the altitude of 6 000 m;NO and NOS mRNA and NOS protein levels were detected in carotid body ofyak and Qaidam yellow cattle living at altitude 3 200 mand simulate-altitude 6 000 m by the realtime quantitative PCR,enzyme-linked immunosorbent assay(ELISA)and immunohistochemical methods.The results showed that the slopes of HVR(△VE/△SaO2)in yaks and Qaidam yellow cattle were(0.21±0.10)and(0.50±0.21)(L·min-1)/% SaO2(P<0.01),respectively;There were no significant differences in the expression of the mRNA and protein of nNOS,eNOS,iNOS in CB between yak and Qaidam yellow cattle at altitude 3 200 m(P>0.05),in the expression of the protein of nNOS,eNOS,iNOS in CB between yak and Qaidam yellow cattle at simulate-altitude 6 000 m(P>0.05),in the expression of the protein of nNOS,eNOS,iNOS in yak CB between simulate-altitude 6 000 mand altitude 3 200 m,nor in Qaidam yellow cattle.The NO of the CB in yak and Qaidam yellow cattle at simulate-altitude 6 000 mwas significantly higher than that of at altitude 3 200 m(P<0.01,P<0.05),respectively.The content of NO in yak CB was significantly higher than that of Qaidam yellow cattle at simulate-altitude 6 000 m(P<0.01).No significant difference in the content of NO in CB between yaks and Qaidam yellow cattle at altitude 3 200 m(P>0.05).The results suggested that HVR was blunted in Yak in Qinghai-Tibetan Plateau,and there was higher ventilatory response to hypoxia in Qaidam yellow cattles,NO production in the yak CB increases during acute hypoxia,and the elevated levels of NO may suppresses the CB response to hypoxia.更多还原