Figure 4. Leptin augmented minute ventilation (V _E) at normoxic conditions (21% O₂) and this effect was abolished by carotid sinus nerve dissection (CSND) in C57BL/6J mice during quiet wakefulness.

A, V _E was calculated as tidal volume per body weight (V _T) × respiratory rate (RR) at 21% O₂ during saline and leptin continuous infusions (120 μg/day, s.c.) measured before (n = 12) and after (n = 9) CSND. B and C, RR (B) and V _T (C) values at the same conditions. ^* P < 0.05, ^** P < 0.01 using the Wilcoxon test for paired comparisons and Mann–Whitney test for unpaired comparisons.