Fig. 3.

Spinal EPAC activation is sufficient to elicit pMF. A: average change in phrenic burst amplitude from baseline. Individual curves represent EPACa-treated rats (10 μl, 100 μM) with saline (◇, n = 7; 10 μl) or with EPACi pretreatment (△, n = 6; 10 μl, 2 mM) or control injections alone (□; n = 20; 10 μl). Data represent mean ± SE values. Significant differences from ^#baseline, *control, or ^&EPACi + 5-HT₇ receptor agonist: all P ≤ 0.05. B: representative phrenic neurograms: time control (i), vehicle + EPACa (ii), or EPACi + EPACa (iii). First arrow represents pretreatment injection; 2nd arrow represents single EPACa injection. Data from control and EPACa groups are shown within multiple figures.