PAGANELLI C V, SOLOMON A K
J Gen Physiol. 1957 Nov 20;41(2):259-77. doi: 10.1085/jgp.41.2.259.
The flow method of reaction rate measurement has been adapted to the determination of the rate of diffusion of water into the human red cell. In seven experiments the half-time for diffusion exchange has been found to be 4.2 +/- 1.1 msec., which is equivalent to a diffusion flow of 8.6 x 10(-9) ml. H(2)O/(sec., red cell). This figure has been compared with the rate of water entrance under an osmotic pressure gradient, and has been found to be smaller by a factor of 2.5. The difference between these two rates of water entrance has been interpreted as indicating the presence of water-filled channels in the membrane. An estimate of the equivalent radius of these channels (on the assumption of uniform right cylindrical pores) leads to a value of 3.5 A, which is viewed as an operational description of the resistance offered by the membrane to the passage of water.
反应速率测量的流动法已被应用于测定水进入人体红细胞的扩散速率。在七次实验中，发现扩散交换的半衰期为4.2±1.1毫秒，这相当于8.6×10⁻⁹毫升H₂O/（秒·红细胞）的扩散流量。该数值已与渗透压梯度下的水进入速率进行了比较，发现其小了2.5倍。这两种水进入速率之间的差异被解释为表明膜中存在充满水的通道。对这些通道等效半径的估计（假设为均匀的直圆柱形孔）得出的值为3.5埃，这被视为对膜对水通过所提供阻力的一种实用描述。
