Albers C, Saborowski F, Usinger W, Scholand C
Respir Physiol. 1975 Jan;23(1):49-57. doi: 10.1016/0034-5687(75)90071-7.
In order to determine mean whole body pHi in unanesthetized dogs, assumptions on the urinary and intestinal excretion of DMO, the total loss of an injected single dose of [14C] DMO, and the distribution kinetics of DMO were tested experimentally. Urinary excretion of DMO was almost negligible. The best assumption on the total loss of DMO was based on the exponential decay observed over a period of 1 to 4 weeks. The biological half-life of DMO was 5 days, the time constant being --0.14 d-1. The extracellular distribution of DMO was considered to equal that of [3H] inulin. Between 1 and 7 hours after an injection of inulin in nephrectomized dogs the distribution volume increased linearly from 16% of the body weight after 2 hours to 21% after 6 hours. Based on these experimental results, pHi was determined in 16 unanesthetized dogs. 120 min after the injection of DMO pHi was 7.05 and 430 min after the injection pHi was 7.11. It is concluded that the assumption made allow the estimation of pHi in unanesthetized dogs over a period of 1 to 7 hours.
为了测定未麻醉犬的平均全身细胞内pH值，对二甲基甘氨酸（DMO）的尿液和肠道排泄、单次注射[14C]DMO的总损失以及DMO的分布动力学进行了实验测试。DMO的尿液排泄几乎可以忽略不计。关于DMO总损失的最佳假设是基于1至4周内观察到的指数衰减。DMO的生物半衰期为5天，时间常数为-0.14 d-1。DMO的细胞外分布被认为与[3H]菊粉的分布相同。在肾切除犬注射菊粉后1至7小时内，分布容积从2小时后的体重的16%线性增加到6小时后的21%。基于这些实验结果，测定了16只未麻醉犬的细胞内pH值。注射DMO后120分钟时细胞内pH值为7.05，注射后430分钟时细胞内pH值为7.11。得出的结论是，所做的假设能够在1至7小时内估算未麻醉犬的细胞内pH值。
