FIGURE 5.

Loss of RTN4a/b reduces SOCE. A and B, increase in cytosolic Ca²⁺ in response to 10 ng/ml PDGF (A) or 1 μm TG (B) in WT and RTN4-KO MEFs in the presence of extracellular Ca²⁺. C, increase in cytosolic Ca²⁺ in response to TG induced depletion of internal stores in the absence of extracellular Ca²⁺. D, SOCE assessed by re-addition of extracellular Ca²⁺ to stores-depleted cells. Inhibition of SOCE was carried out in WT MEFs exposed to vehicle or CRAC inhibitors 2APB (50 μm) or gadolinium (10 μm). A–D, calcium traces represent the average response of 25–30 cells per triplicate from a single experiment. F/F₀, change in fluorescence intensity relative to baseline. Areas under the curve were calculated after treatment or re-addition of external Ca²⁺. Data represent the mean ± S.E. of 4–6 independent experiments. *, p < 0.05 compared with WT MEFs, Student's t test.