Kawashiro T, Carles A C, Perry S F, Piiper J
Pflugers Arch. 1975 Sep 9;359(3):219-30. doi: 10.1007/BF00587381.
Krogh's diffusion constant (K) was determined for various inert gases in isolated rat abdominal muscle at 37 degrees C by measuring the amount of gas diffusing per unit time and partial pressure difference through a portion of the muscle of known surface area and thickness. The following mean values for K, in 10(-9) mmol-min-1-cm-1-torr-1, were obtained: C2H2, 42.2; N2O, 20.0; CHClF2, 18.8; H2, 1.67; He, 1.42; CH4, 1.27; SF6, 0.081. From Krogh's diffusion constant, the diffusion coefficient (D) was calculated using the solubility coefficient determined previously in the same preparation. The D values thus obtained were found to be about half the D values in water at 37 degrees C. Model calculations show that for gases with high lipid/water partition coefficient, D in tissues containing lipid is underestimated by this method. Graham's law (inverse proportionality between D and square root of molecular mass) was found to represent a useful approximation for these gases. A better correlation, however, was obtained between D and the molecular diameter.
在37摄氏度下，通过测量单位时间内通过已知表面积和厚度的部分肌肉扩散的气体量以及分压差，确定了离体大鼠腹肌中各种惰性气体的克罗格扩散常数（K）。得到了以下K的平均值，单位为10^(-9) mmol·min^(-1)·cm^(-1)·torr^(-1)：乙炔，42.2；一氧化二氮，20.0；二氟一氯甲烷，18.8；氢气，1.67；氦气，1.42；甲烷，1.27；六氟化硫，0.081。根据克罗格扩散常数，利用先前在同一制剂中测定的溶解度系数计算扩散系数（D）。结果发现，由此获得的D值约为37摄氏度时水中D值的一半。模型计算表明，对于具有高脂质/水分配系数的气体，这种方法会低估含脂质组织中的D值。发现格拉罕姆定律（D与分子量平方根成反比）对这些气体是一个有用的近似。然而，D与分子直径之间的相关性更好。
