犬肾切片中钾的跨膜通量。热缺血影响的定量分析。

Transmembrane fluxes of potassium in dog kidney slices. A quantitation of the effect of warm ischemia.

作者信息

Nauclér J, Jonsson O, Lundstam S, Pettersson S, Scherstén T, Stage L

出版信息

Eur Surg Res. 1977;9(5):384-96. doi: 10.1159/000127957.

Abstract

The effect of warm ischemia on the transmembrane transport of potassium in dog kidney slices was studied by measurement of the uptake of 42K. The requirement for steady-state conditions concerning the intracellular potassium concentration was thereby studied. The total potassium content in the slices was found to be constant between 120 and 180 min incubation at both 25 and 37 degrees C. The cell water calculated from the total tissue water and 14C-inulin space in the dog kidney slices amounted to 38 ml-100 g wet weight-1 at 37 degrees C and 45 ml-100 g wet weight-1 at 25 degrees C and was found to remain constant for the incubation interval 120--180 min. The major part of the tissue uptake of 42K could be described by one single mono-exponential function under these conditions. The transmembrane influx at 37 degrees C calculated by using a modified Keynes formula amounted to 1.70 mmol K+-kg wet weight-1-min-1 after no warm ischemia and to 0.89 mmol K+-kg wet weight-1-min-1 after 2 h warm ischemia. The corresponding values for incubation at 25 degrees C were 1.26 and 0.77 mmol K+-kg wet weight-1-min-1, respectively. In the slices incubated at 25 degrees C, the potassium content was higher and the sodium content lower than in slices incubated at 37 degrees C.

摘要

通过测量⁴²K的摄取量，研究了热缺血对犬肾切片中钾跨膜转运的影响。由此研究了细胞内钾浓度达到稳态条件的要求。发现在25℃和37℃孵育120至180分钟期间，切片中的总钾含量保持恒定。根据犬肾切片中的总组织水和¹⁴C-菊粉空间计算出的细胞内水量，在37℃时为38 ml·100 g湿重⁻¹，在25℃时为45 ml·100 g湿重⁻¹，并且发现在120 - 180分钟的孵育间隔内保持恒定。在这些条件下，组织对⁴²K的摄取大部分可用一个单一的单指数函数来描述。使用改良的凯恩斯公式计算，在37℃时，无热缺血后的跨膜流入量为1.70 mmol K⁺·kg湿重⁻¹·min⁻¹，热缺血2小时后为0.89 mmol K⁺·kg湿重⁻¹·min⁻¹。在25℃孵育的切片中，相应的值分别为1.26和0.77 mmol K⁺·kg湿重⁻¹·min⁻¹。在25℃孵育的切片中，钾含量高于在37℃孵育的切片，而钠含量低于在37℃孵育的切片。