Gonzalez N C, Perry K, Moue Y, Clancy R L, Piiper J
Department of Physiology, University of Kansas Medical Center, Kansas City 66160-7401.
Respir Physiol. 1994 May;96(2-3):111-25. doi: 10.1016/0034-5687(94)90120-1.
Pulmonary gas exchange and O2 transport were studied at rest and during maximal treadmill exercise in rats in acute hypoxia (PIO2 approximately 71 Torr), and in littermates acclimatized to PB = 380 Torr (PIO2 approximately 71 Torr) for 3 weeks (chronic hypoxia). To obtain valid estimates of blood gas partial pressures, particularly during exercise, the temperature coefficients of blood pH, PO2 and PCO2 were determined (Appendix). In both acute and chronic hypoxia, the following changes were observed: alveolar and arterial PO2 increased considerably, but the difference, A-aPO2, did not change significantly; arterial O2 concentration (CaO2) decreased, and apparent pulmonary diffusing capacity for O2, Dapp, increased. The increase in Dapp, together with hyperventilation, may prevent further drop in CaO2 due to a large rightward shift in the blood-O2 equilibrium curve caused by lactic acidosis in conjunction with a large Bohr coefficient characteristic of this species. Comparison with corresponding results obtained in man reveals that during hypoxic exercise, the rat shows a larger increase in PAO2, an increase, instead of a decrease, in PaO2, and a larger increase in Dapp.
在急性低氧（吸入氧分压约71托）的大鼠以及在3周内适应于380托（吸入氧分压约71托）的同窝幼鼠（慢性低氧）中，研究了静息状态和最大强度跑步机运动期间的肺气体交换和氧气运输。为了获得血气分压的有效估计值，特别是在运动期间，测定了血液pH、氧分压和二氧化碳分压的温度系数（附录）。在急性和慢性低氧中，观察到以下变化：肺泡和动脉氧分压显著升高，但差值（A-aPO₂）无显著变化；动脉血氧浓度（CaO₂）降低，表观肺氧扩散容量（Dapp）增加。Dapp的增加与过度通气一起，可能由于乳酸酸中毒导致血液氧平衡曲线大幅右移以及该物种特有的大波尔系数，从而防止CaO₂进一步下降。与在人类中获得的相应结果相比，发现在低氧运动期间，大鼠的肺泡氧分压升高幅度更大，动脉氧分压升高而非降低，并且Dapp升高幅度更大。
