Figure 4.

F-actin is required for osmosensory transduction. A, Whole-cell current-clamp recordings from isolated MNCs subjected to hypertonic stimuli (bar; +60 mosmol/kg). The traces show representative recordings taken from cells treated with vehicle (control, top), Cyt-D (middle), and JSK (bottom). In all traces, the spikes are truncated and the dashed line indicates −55 mV. B, Bar graphs showing that mean (±SEM) osmoreceptor potentials (depolarization measured at 60 s; middle) and excitation (increase in firing observed between 50 and 70 s compared with control; right) were significantly reduced by Cyt-D and significantly enhanced by JSK, whereas no difference was noted in the amount of shrinking evoked by the osmotic stimulus (p = 0.923; measured 60 s after stimulus onset; left). *p < 0.05.