Figure 4. Activation of PAG^LepRb increases adrenal SNA, blood glucose, and respiratory responses to hypercapnia.

(A) Lepr^Cre (CC) animals were injected with AAV-hM3Dq into the PBN (left panels) or PAG (right panels). (B and C) PBN (B) (n = 8, C57BL/6 [C57]; n = 6, CC) and PAG (C) (n = 7, C57BL/6; n = 9, CC) AAV-hM3Dq–injected C57BL/6 or Lepr^Cre (Cre) animals were treated with CNO during SNA recording. Data were broken down into 5-minute bins for analysis; data are plotted as mean ± SEM; *P < 0.05. (D and E) PBN (D) or PAG (E) AAV-hM3Dq–injected Lepr^Cre mice were injected with either CNO or vehicle and blood glucose sampled. Data are presented as mean ± SEM; *P < 0.05. (F) PAG-injected Lepr^Cre mice were treated with either CNO or vehicle, and respiratory frequency was monitored at baseline and during exposure to 3% CO₂ in a whole-body plethysmograph. Data are plotted as mean ± SEM; *P < 0.05. Data in panels B–E were analyzed by 2-way repeated-measures ANOVA with Fisher’s LSD post hoc test. Data in panel F were analyzed using a 1-tailed t test.