Department of Physiology, School of Medicine, the Johns Hopkins University, Baltimore.
J Gen Physiol. 1926 Jul 20;9(6):813-26. doi: 10.1085/jgp.9.6.813.
It is obvious that the factors considered in this paper render data obtained by ultrafiltration open to criticism unless they are checked by other methods and precautions are taken for the elimination of the vitiating effects which have been described. As regards the mechanism of ultrafiltration, the view of a sieve-like action as most experimental evidence indicates, is adequate, if all the factors are considered which might modify the effective pore size. The behaviors of collodion membranes which seem contrary to a mechanism of ultrafiltration based on the existence of a system of pores, can be explained on the basis of a variable layer of adsorbed fluid on the walls of the pores. It is, therefore, unsound to make any deductions about living tissues from the demonstration of changes produced in the behavior of collodion membranes. Thus, the increase in the rate of filtration of water through collodion by diuretics (29) or the change of permeability due to the presence of surface-active materials, gives us no information about their action in the living organism. The effect of these substances on a sieve-like membrane of the type of collodion would not necessarily bear any analogy to that exerted on the emulsion type of membrane of living cells. The mechanisms of the reactions necessary to produce the same effects in such widely differing systems may be entirely unrelated.
很明显，本文中考虑的因素使得通过超滤获得的数据容易受到批评，除非通过其他方法进行检查，并采取措施消除已经描述的有害影响。就超滤的机制而言，如果考虑到所有可能改变有效孔径的因素，那么最实验证据表明的筛状作用的观点是充分的。似乎与基于孔系统的超滤机制相悖的胶膜行为，可以根据孔壁上吸附的流体的可变层来解释。因此，从胶膜行为变化的证明中推断出关于活组织的任何结论都是不合理的。因此，利尿剂（29）增加水通过胶膜的过滤速度或由于表面活性剂的存在而改变渗透性，都不能说明它们在活生物体中的作用。这些物质对胶膜类型的筛状膜的作用不一定与对活细胞的乳剂类型的膜的作用有任何相似之处。在如此不同的系统中产生相同效果所需的反应机制可能完全没有关系。
