Fig. 7.

Effect of RVLM CRF receptor blockade on PVN-driven sympathetic activation by glucose. A: representative responses of lumbar SNA, splanchnic SNA, and ABP to bilateral RVLM injection of aCSF (top) or astressin (bottom) prior to iv glucose infusion and PVN injection of muscimol. B: corresponding summary data showing that PVN inhibition with muscimol restored glucose-stimulated lumbar SNA and splanchnic SNA while also reducing MAP in rats pretreated with aCSF in the RVLM. In contrast, PVN inhibition had no effect when glucose responses were prevented by prior RVLM injection of astressin. C: schematic drawings of 3 rostrocaudal coronal planes through the PVN showing the location of injected muscimol in rats infused with saline (gray; left) and glucose (black; right). The period of glucose infusion is indicated in each part by the black horizontal bar along the x-axis. *P < 0.05 vs. saline; ‡P < 0.05 vs. 30 min.