Figure 8

K⁺-dependence of NCXs in TG neurons. (A) Representative trace of an increase in [Ca²⁺]_i by substituting Na⁺-ECS with Li⁺-ECS while maintaining osmotic strength by replacing NaCl with LiCl, with or without application of 5.0 mM [K⁺]_o. Applied solution-changing protocol for [Na⁺]_o, [Li⁺]_o and [Ca²⁺]_o is shown in upper grey boxes; protocol for [K⁺]_o is shown in lower black boxes. (B) Summary bar graphs of increase in [Ca²⁺]_i by application of Li⁺-ECS without (open column) or with (black column) 5.0 mM extracellular K⁺. Each bar denotes mean ± S.E. of number of separate experiments (numbers in parentheses represent number of tested cells). No statistically significant difference in F/F₀ values was observed between Li⁺-ECS without or with 5.0 mM K⁺.