Figure 6.

The effect of AA release inhibition on orexin-induced receptor-operated Ca²⁺ influx (A, C) and Ca²⁺ release (B, D) in CHO-hOX₁ cells in NaBM. (A, C) Cells are over-expressing IP₃-5P1, which precludes Ca²⁺ release. In (A) data from counting of responsive and non-responsive cells (n= 458–496 cells/treatment) and in (C) a representative experiment (n= 29–31 cells/trace). Some error bars (C) are omitted for purpose of clarity. (B, D) Cells were stimulated in nominally Ca²⁺-free conditions (no CaCl₂ added to the NaBM), which gives an extracellular [Ca²⁺]≈ 2.5–3.3 µM as measured using CalciumGreen 5N, which is low enough concentration to abolish the Ca²⁺ influx. In (B) data from counting of responsive and non-responsive cells (n= 551–577 cells/treatment) and in (D) the average Ca²⁺ responses from these cells. The first comparisons (*/**/***) in (A, B and D) are to the basal (i.e. Does orexin cause a Ca²⁺ response?) and the second comparison (††† and ns) to the corresponding orexin response (i.e. Does MAFP inhibit the response to orexin-A?); ns (not significant), P > 0.05; **P < 0.01; ***P < 0.001, †††P < 0.001.