Abstract
Characean internodal cells generate receptor potential in response to mechanical stimuli. The mechano-peception was studied in characeaean internodal cells. In this study, cells were stimulated by compressing them for 10 s with an acrylic stick. The responses of internodal cells to the compression was as follows. (1) The cell generated receptor potential at the both moments of compression and decompression. (2) The ΔEm was significantly larger at the decompression than at the compression. Aequrorin studies revealed that the increase in [Ca2+]c (Δ[Ca2+]c) took place at both moments. The amplitude of Δ[Ca2+]c was smaller at the compression than at the decompression, as was the case in ΔEm. We discussed the ionic mechanism of mechano-perception under long term compression in relation with mechanosensitive activation of Ca2+ channels at the plasma membrane.
