Figure 11. Effects of ouabain on releasable endoplasmic reticulum Ca²⁺ stores in astrocytes.

A, F₃₆₀/F₃₈₀ ratio data from a representative astrocyte in which the Ca²⁺ transients were evoked by 10 μm CPA + 10 mm CAF in Ca²⁺-free medium; the cell responded robustly to 0.5 μm ATP but only slightly to 4 μm Glu. The response to CPA + CAF was tested before ouabain and immediately after a 4 min pretreatment with 3 nm ouabain. B, averaged maximal increase (+SEM) in ΔF₃₆₀/F₃₈₀ in response to ATP and to CPA+CAF before and immediately after 3 nm ouabain, from experiments similar to the one shown in A. n = 14 cells; **P < 0.01 vs.‘before’ and ‘after’ ouabain (ANOVA).