Sr and Ba transients in isolated snail neurones studied with fura-2. The recovery from depolarization induced load and modulation of Ca release from intracellular stores.

The fluorescent Ca-sensitive probe fura-2 was used in isolated non-identified neurons of the snail, Helix pomatia, to study the recovery from Sr and Ba loading and the effect of these cations on Ca-induced Ca release. Sr was shown to behave similarly to Ca, whereas Ba ions were not sequestered within the cell. Intracellular Ba blocked both the voltage-gated channels in the plasma membrane and the Ca release channels in the membrane of intracellular stores.