Kinney J L, Matsuura D T, White F N
Respir Physiol. 1977 Dec;31(3):309-25. doi: 10.1016/0034-5687(77)90074-3.
Weight specific VO2 of resting Pseudemys floridana at body temperatures (BT) between 12 to 38 C was studied in relationship to VE, VT, f, pulmonary and systemic blood flow, and blood PO2, PCO2, pH and O2 content. The slope of the curve for VO2 against body mass was similar to that for mammals and differed from that of lizards. VE increased with BT while VE/VO2 fell, resulting in an elevation of arterial PCO2 and a decline in arterial pH of 0.013 unit/degrees C [HCO-3] and total CO2 remained constant. Increments in VE were achieved by decreasing apneic time and increasing VT up to VT of 18 ml.kg-1 when further rise in VE was exclusively on account of breathing frequency. Mean pulmonary and arterial blood flows were incremented in direct proportion to VO2, and no net intracardiac shunts was demonstrable. Ventilation-perfusion ratio fell with BT while EO2 increased. Arterial hemoglobin saturation varied inversely with BT while the arteriovenous O2 difference remained constant. EO2 was found to be highly dependent on the constant blood convection requirement as VE/VO2 fell. At similar BT, VE/VO2 was similar to that for man while Qpul/VO2 was in inverse proportion to maximum O2 capacity of the blood for the two species.
研究了体温（BT）在12至38摄氏度之间的静止佛罗里达伪龟的体重特异性耗氧量与每分钟通气量（VE）、潮气量（VT）、呼吸频率（f）、肺血流量和体循环血流量，以及血液中的氧分压（PO2）、二氧化碳分压（PCO2）、pH值和氧含量之间的关系。耗氧量（VO2）相对于体重的曲线斜率与哺乳动物的相似，与蜥蜴的不同。每分钟通气量随体温升高而增加，而每分钟通气量与耗氧量的比值（VE/VO2）下降，导致动脉血二氧化碳分压升高，动脉血pH值以每摄氏度0.013单位的幅度下降，[HCO3-]和总二氧化碳含量保持不变。每分钟通气量的增加是通过缩短呼吸暂停时间和增加潮气量来实现的，直至潮气量达到18 ml.kg-1，此时每分钟通气量的进一步增加完全是由于呼吸频率的增加。平均肺血流量和动脉血流量与耗氧量成正比增加，且未发现明显的心内分流。通气/血流比值随体温升高而下降，而氧提取率（EO2）增加。动脉血红蛋白饱和度与体温呈反比变化，而动静脉氧差保持不变。由于VE/VO2下降，发现氧提取率高度依赖于恒定的血液对流需求。在相似的体温下，VE/VO2与人类的相似，而肺血流量与耗氧量的比值（Qpul/VO2）与这两个物种血液的最大氧容量成反比。
