Fig. 4.
Bilateral [D-Ala,2 N-MePhe,4 Gly-ol]-enkephalin (DAMGO) injection into the “tachypneic area” of the parabrachial nucleus (tPBN) had a significantly different effect on respiratory timing and drive compared to the pre-Bötzinger complex (preBötC). Values are displayed as mean ± SD for inspiratory duration (TI; A), expiratory duration (TE; B), respiratory rate (C), and respiratory drive (D). Note differences in scale for TI and TE. Values on the left are from our previous study in the preBötC, and values on the right are from our current tPBN study. For preBötC, gray bars: young (n = 8); white bars: adult (n = 16). For tPBN, gray bars: young (n = 14); white bars: adult (n = 11). *P < 0.05, **P < 0.01, and ***P < 0.001 indicate significant differences in DAMGO effect between studies (linear mixed model, factors: study, drug application, and developmental age).