Rapoport S I, Peachey L D, Goldstein D A
J Gen Physiol. 1969 Aug;54(2):166-77. doi: 10.1085/jgp.54.2.166.
Electron microscopy shows that the transverse tubular system of frog sartorius swells in Ringer fluid in which NaCl is partially replaced by sucrose (sucrose isotonic solutions). At constant tonicity, the degree of swelling is roughly proportional to the decrease in ionic strength and to the sucrose concentration of the bathing solution. Swelling is time-dependent and reversible within 2 hr. The late after potential which follows a train of impulses is prolonged with swelling, but not to the extent expected from the model of Adrian and Freygang. This discrepancy remains unexplained, as does the mechanism of swelling of the transverse tubular system, although some suggestions are offered. One is that the transverse tubular system contains fixed charges and swells like a fixed charge gel.
电子显微镜显示，在林格液中，当氯化钠部分被蔗糖替代（蔗糖等渗溶液）时，青蛙缝匠肌的横管系统会肿胀。在等渗条件下，肿胀程度大致与离子强度的降低以及浴液中蔗糖浓度成正比。肿胀具有时间依赖性，且在2小时内是可逆的。一连串冲动之后出现的后电位会随着肿胀而延长，但延长程度未达到阿德里安和弗雷冈模型所预期的程度。这种差异以及横管系统肿胀的机制均未得到解释，不过文中提出了一些推测。一种推测是，横管系统含有固定电荷，像固定电荷凝胶一样发生肿胀。
