Variation in the ISM Na I D resonant line profile as a function of galaxy inclination, for the galaxies with SFR ≥ 10^1.1 M_⊙ yr⁻¹ (including pure SF galaxies and galaxies with an AGN contribution). The line is centred to the systemic velocity in the edge-on sample and shows a progressive blueshift as the mean disc inclination decreases. The maximum shift is reached by face-on galaxies (blue curve).