de Gaetano A, Mingrone G, Castagneto M, Benedetti G, Greco A V, Gasbarrini G
Biomathematics Laboratory, Consiglio Nazionale delle Ricerche, Centro Fisiopatologia Shock, Università Cattolica, 8-00168 Rome, Italy.
Am J Physiol. 1999 Mar;276(3):E497-502. doi: 10.1152/ajpendo.1999.276.3.E497.
The kinetics of the triglyceride of dodecanedioic acid (TGDA) has been investigated in 30 male Wistar rats after a rapid intravenous bolus injection. TGDA and its product of hydrolysis, nonesterified dodecanedioic acid (NEDA), were measured in plasma samples taken at different times using an improved high-performance liquid chromatographic method. The 24-h urinary excretion of TGDA was 1.54 +/- 0.37 micromol, corresponding to approximately 0.67% of the administered amount. Several kinetics models were considered, including central and peripheral compartments for the triglyceride and the free forms and expressing transports between compartments with combinations of linear, carrier-limited, or time-varying mechanisms. The parameter estimates of the kinetics of TGDA and of NEDA were finally obtained using a three-compartment model in which the transfer of TGDA to NEDA was assumed to be linear, through a peripheral compartment, and the tissue uptake of NEDA was assumed to be carrier limited. TGDA had a large volume of distribution ( approximately 0.5 l/kg body wt) with a fast disappearance rate from plasma (0.42 min-1), whereas NEDA had a very small volume of distribution ( approximately 0.04 l/kg body wt) and a tissue uptake with maximal transport rate of 0.636 mM/min. In conclusion, this first study on the triglyceride form of dodecanedioic acid indicates that it is rapidly hydrolyzed and that both triglyceride and nonesterified forms are excreted in the urine to a very low extent. The tissue uptake rate of NEDA is consistent with the possibility of achieving substantial energy delivery, should it be added to parenteral nutrition formulations. Furthermore, the amount of sodium administered with the triglyceride form is one-half of that necessary with the free diacid.
在30只雄性Wistar大鼠快速静脉推注后,对十二烷二酸甘油三酯(TGDA)的动力学进行了研究。使用改进的高效液相色谱法,在不同时间采集的血浆样本中测量了TGDA及其水解产物非酯化十二烷二酸(NEDA)。TGDA的24小时尿排泄量为1.54±0.37微摩尔,约占给药量的0.67%。考虑了几种动力学模型,包括甘油三酯及其游离形式的中央和外周隔室,并以线性、载体限制或时变机制的组合表示隔室之间的转运。最终使用三室模型获得了TGDA和NEDA动力学的参数估计值,其中假设TGDA通过外周隔室向NEDA的转化是线性的,并且假设NEDA的组织摄取是载体限制的。TGDA具有较大的分布容积(约0.5升/千克体重),从血浆中消失的速率较快(0.42分钟-1),而NEDA的分布容积非常小(约0.04升/千克体重),组织摄取的最大转运速率为0.636毫摩尔/分钟。总之,这项关于十二烷二酸甘油三酯形式的首次研究表明,它会迅速水解,并且甘油三酯和非酯化形式在尿液中的排泄程度都非常低。NEDA的组织摄取率与如果将其添加到肠外营养制剂中实现大量能量输送的可能性一致。此外,与甘油三酯形式一起给药的钠量是游离二酸所需量的一半。