摘要
通气不足会引起肺血管收缩、减少血流量以协调通气／血流比值，从而有助于动脉血氧分压的维持。本实验的目的是了解机体是否存在反向调节，肺血流减少能否引起气道收缩。在离体灌注大鼠肺实验，肺循环灌注量减少７０～９０％，１ｍｉｎ时肺阻力有所下降。在整体家兔实验，用气囊阻断下腔静脉血流使肺循环灌注量减少１２～３０％，肺阻力由６．６５±１．４９下同）降至６．４８±１．６１（３ｍｉｎ时）和６．４０±１．７４（５ｍｉｎ时）Ｐａ·ｓ／ｍｌ，Ｐ＜０．０５，配对ｔ检验。由此可见，肺血流量的减少不能通过收缩气道而引起通气量减少，机体在维持肺通气／血流比值的机制中可能不存在双向调节。
As well known that alveolar hypoventilaon leads to pulmonaryvasoconstriction to maintain the ventilation-perfusion balanee. It was imagined thatpulmonary hypoperfusion could result in alveolar hypoventilation by causingconstriction of the airway. Unexpectedly we found that reduction of the pulmonaryperfusion by 70～90 % in isolated-perfused rat lungs decreased lung resistance. Similarresults were obtitined in rabbits in vivo by obstructing the vena cava inferior with anintravascular gas ballon to reduce the pulmonary perfusion by 12～30%, the lung resisttince decreased from 6.65±1.49 to 6.48 ±1.61(3min)and 6.40±1.74(5min) Pa·s/ml,P<0.05.paired t test.It seemed that pulmonary hypoperfusion didn' t cause airwayconstriction.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
1996年第2期155-158,共4页
Chinese Journal of Pathophysiology
关键词
肺循环
气道阻力
通气灌注
Pulmonary circulation·Ajrway resistance·Ventilation-perfusion ratio
