CAJ | 학술논문

目的研究模拟失重对离体大鼠肺血管调节功能的影响,旨在探讨模拟失重对肺循环的影响和立位耐力降低的发生机制. 方法采用尾部悬吊(TS)大鼠模拟失重生理效应.24只健康雄性Wistar大鼠随机分为对照组、TS 7 d和TS 14 d共3组.采用离体肺灌流技术,利用Power-lab生理系统记录恒流下大鼠肺循环灌注压的变化,并分别于苯肾上腺素(PE)、乙酰胆碱(Ach)和硝普钠(SNP)药物干预后,观察离体肺血管反应性,并计算出肺血管阻力. 结果与对照组相比,TS7 d和TS 14 d大鼠离体肺在恒流灌注下肺动脉压明显降低(F=3.58～20.86,P<0.05或P<0.01),离体大鼠肺动脉血管对PE的收缩反应明显下降,对Ach和SNP的舒张反应明显增强,同时肺血管阻力也相应降低(F=3.56～20.44,P<0.05或P<0.01). 结论尾吊大鼠离体肺血管灌注压降低,血管收缩反应性降低、舒张反应性增强,肺血管阻力减弱,尾吊模拟失重大鼠肺循环血管调节功能减弱,对失重后立位耐力不良有一定的影响.
목적 연구모의실중대리체대서폐혈관조절공능적영향,지재탐토모의실중대폐순배적영향화립위내력강저적발생궤제. 방법채용미부현조(TS)대서모의실중생리효응.24지건강웅성Wistar대서수궤분위대조조、TS 7 d화TS 14 d공3조.채용리체폐관류기술,이용Power-lab생리계통기록항류하대서폐순배관주압적변화,병분별우분신상선소(PE)、을선담감(Ach)화초보납(SNP)약물간예후,관찰리체폐혈관반응성,병계산출폐혈관조력. 결과여대조조상비,TS7 d화TS 14 d대서리체폐재항류관주하폐동맥압명현강저(F=3.58～20.86,P<0.05혹P<0.01),리체대서폐동맥혈관대PE적수축반응명현하강,대Ach화SNP적서장반응명현증강,동시폐혈관조력야상응강저(F=3.56～20.44,P<0.05혹P<0.01). 결론미조대서리체폐혈관관주압강저,혈관수축반응성강저、서장반응성증강,폐혈관조력감약,미조모의실중대서폐순배혈관조절공능감약,대실중후립위내력불량유일정적영향.
Objective To study the effects of simulated microgravity on regulative function of isolated perfused pulmonary arteries in rats, in order to investigate the mechanism of the changes of pulmonary circulation and poor orthostatic tolerance under simulated microgravity environment.Methods Tail-suspension (TS) rats were used as the animal model to simulate the physiological effects of microgravity. Twenty-four healthy male Wistar rats were randomly divided into 3 groups:control group (CON), TS for 7 d(TS 7 d) and TS14d. The changes of the regulative function of pulmonary arteries to several vasoactive agents were measured by using the perfusion technique of isolated lung and the data were recorded by Powerlab system. Results Compared with the control group, the perfused pressure of the isolated pulmonary arteries decreased significantly in TS 7 d and TS 14 d groups (F=3.58～20.86, P<0.05 or P<0.01), the contractile responses of pulmonary arteries to phenylephrine(PE) declined in TS 14 d, while the vasodilator responses to acetylcholine(Ach) and sodium nitroprusside (SNP) were markedly enhanced. Moreover, pulmonary vascular resistance(PVR) decreased significantly in TS 7d and TS 14 d rats (F= 3.56～20.44, P<0.05 or P<0.01). Conclusion The isolated pulmonary arteries in TS rats under microgravity showsdecreased perfused pressure and contractile response but increased vasodilator responsiveness, while isolated perfusion PVR attenuated. The impaired regulative functions of pulmonary arteries may influence orthostatic intolerance.