Darrah P S, Beitz D C, Topel D G, Christian L L
J Anim Sci. 1981 Oct;53(4):1000-5. doi: 10.2527/jas1981.5341000x.
In vitro rates of lactate metabolism were determined in stress-susceptible (SS) and stress-resistant (SR) pigs. Three SR and three SS pigs were given 20 muCi of [U-14C] L-lactate by a single injection method and resting blood lactate kinetics were measured. Seventeen blood samples were taken during the 60 min after injection. Lactate was separated from the deproteinized plasma by silicic acid column chromatography, and specific radioactivity was determined. Kinetic characteristics were calculated from plots of specific activity versus time. Pigs met steady-state requirements during the sampling period. There were no differences in kinetic characteristics of resting SS and SR pigs. Later, a second isotope injection was given after 5 min of electrical stress. Lactate pool sizes increased similarly in both types of pigs after stress; however, SS pigs had greater plasma lactate concentrations after stress. It is concluded that SS and SR pigs respond differently to stress but have similar capacities to metabolize lactate while resting.
在应激敏感（SS）猪和应激抗性（SR）猪中测定了体外乳酸代谢率。通过单次注射法给3头SR猪和3头SS猪注射20微居里的[U-14C]L-乳酸，并测量静息血乳酸动力学。注射后60分钟内采集了17份血样。通过硅酸柱色谱法从脱蛋白血浆中分离出乳酸，并测定比放射性。根据比活性与时间的曲线计算动力学特征。猪在采样期间满足稳态要求。静息的SS猪和SR猪的动力学特征没有差异。随后，在电应激5分钟后进行第二次同位素注射。应激后两种类型的猪乳酸池大小增加相似；然而，应激后SS猪的血浆乳酸浓度更高。得出的结论是，SS猪和SR猪对应激的反应不同，但在静息时代谢乳酸的能力相似。
