Chronic intermittent hypobaric hypoxia(CIHH)is known to have an anti-hypertensive effect, which might be related to modulation of the baroreflex in rats with renal vascular hypertension(RVH). In this study, RVH was in...Chronic intermittent hypobaric hypoxia(CIHH)is known to have an anti-hypertensive effect, which might be related to modulation of the baroreflex in rats with renal vascular hypertension(RVH). In this study, RVH was induced by the 2-kidney-1-clip method(2 K1 C) in adult male Sprague-Dawley rats. The rats were then treated with hypobaric hypoxia simulating 5000 m altitude for 6 h/day for 28 days. The arterial blood pressure(ABP), heart rate(HR), and renal sympathetic nerve activity(RSNA) were measured before and after microinjection of L-arginine into the nucleus tractus solitarii(NTS) in anesthetized rats.Evoked excitatory postsynaptic currents(eEPSCs) and spontaneous EPSCs(sEPSCs) were recorded in anterogradely-labeled NTS neurons receiving baroreceptor afferents. We measured the protein expression of neuronal nitric oxide synthase(nNOS) and endothelial NOS(eNOS) in the NTS. The results showed that the ABP in RVH rats was significantly lower after CIHH treatment. The inhibition of ABP, HR, and RSNA induced by L-arginine was less in RVH rats than in sham rats, and greater in the CIHHtreated RVH rats than the untreated RVH rats. The eEPSC amplitude in NTS neurons receiving baroreceptor afferents was lower in the RVH rats than in the sham rats and recovered after CIHH. The protein expression of nNOS and e NOS in the NTS was lower in the RVH rats than in the sham rats and this decrease was reversed by CIHH. In short, CIHH treatment decreases ABP in RVH rats via upregulating NOS expression in the NTS.展开更多
目的建立稳定的大鼠肾神经放电记录的方法学及探讨急性阻塞性睡眠呼吸暂停模型下的左侧肾交感神经活性(RSNA)变化.方法成年雄性SD大鼠10只,麻醉后气管插管,反复间歇夹闭气管导管20 s,同步记录大鼠RSNA、心率和动脉血压的变化.结果所有...目的建立稳定的大鼠肾神经放电记录的方法学及探讨急性阻塞性睡眠呼吸暂停模型下的左侧肾交感神经活性(RSNA)变化.方法成年雄性SD大鼠10只,麻醉后气管插管,反复间歇夹闭气管导管20 s,同步记录大鼠RSNA、心率和动脉血压的变化.结果所有大鼠均在实验中记录到稳定的RSNA、心率及血压图形,并完成了整个实验过程.与闭气前20 s相比,闭气期间:①RS N A的频率从(0.40±0.26)次增加到(9.30±3.92)次(P<0.05);②RSNA的电压从(0.02±0.00)mV增加到(0.03±0.01)mV(P<0.01);③RR间期从(208.48±15.30)m s增加到(224.00±49.75)m s(P<0.05);④血压明显从(122.05±9.82)m m H g下降为(109.71±7.51)m m H g(P<0.01).结论闭气期间RSNA明显增强,RR间期下降,血压明显下降.展开更多
基金supported by the National Natural Science Foundation of China(31071002,31271223,31671184,and 81800308)the National Basic Research Development Program of China(2012CB518200)the Natural Science Foundation of Hebei Province(C2012206001),China
文摘Chronic intermittent hypobaric hypoxia(CIHH)is known to have an anti-hypertensive effect, which might be related to modulation of the baroreflex in rats with renal vascular hypertension(RVH). In this study, RVH was induced by the 2-kidney-1-clip method(2 K1 C) in adult male Sprague-Dawley rats. The rats were then treated with hypobaric hypoxia simulating 5000 m altitude for 6 h/day for 28 days. The arterial blood pressure(ABP), heart rate(HR), and renal sympathetic nerve activity(RSNA) were measured before and after microinjection of L-arginine into the nucleus tractus solitarii(NTS) in anesthetized rats.Evoked excitatory postsynaptic currents(eEPSCs) and spontaneous EPSCs(sEPSCs) were recorded in anterogradely-labeled NTS neurons receiving baroreceptor afferents. We measured the protein expression of neuronal nitric oxide synthase(nNOS) and endothelial NOS(eNOS) in the NTS. The results showed that the ABP in RVH rats was significantly lower after CIHH treatment. The inhibition of ABP, HR, and RSNA induced by L-arginine was less in RVH rats than in sham rats, and greater in the CIHHtreated RVH rats than the untreated RVH rats. The eEPSC amplitude in NTS neurons receiving baroreceptor afferents was lower in the RVH rats than in the sham rats and recovered after CIHH. The protein expression of nNOS and e NOS in the NTS was lower in the RVH rats than in the sham rats and this decrease was reversed by CIHH. In short, CIHH treatment decreases ABP in RVH rats via upregulating NOS expression in the NTS.
基金supported by the National Natural Science Foundation of China(No.81170069)the Science and Technology Research Project of Colleges and Universities in Hebei Province of China(No.ZD2017057)Doctoral Fund of Hebei University of Chinese Medicine(No.BSE2017014)
文摘目的建立稳定的大鼠肾神经放电记录的方法学及探讨急性阻塞性睡眠呼吸暂停模型下的左侧肾交感神经活性(RSNA)变化.方法成年雄性SD大鼠10只,麻醉后气管插管,反复间歇夹闭气管导管20 s,同步记录大鼠RSNA、心率和动脉血压的变化.结果所有大鼠均在实验中记录到稳定的RSNA、心率及血压图形,并完成了整个实验过程.与闭气前20 s相比,闭气期间:①RS N A的频率从(0.40±0.26)次增加到(9.30±3.92)次(P<0.05);②RSNA的电压从(0.02±0.00)mV增加到(0.03±0.01)mV(P<0.01);③RR间期从(208.48±15.30)m s增加到(224.00±49.75)m s(P<0.05);④血压明显从(122.05±9.82)m m H g下降为(109.71±7.51)m m H g(P<0.01).结论闭气期间RSNA明显增强,RR间期下降,血压明显下降.
