Fig. 1.

Blockade of paraventricular nucleus (PVN) neuropeptide Y (NPY) Y1R (NPY1x) prevents further increases in lumbar sympathetic nerve activity (LSNA) induced by arcuate nucleus (ArcN) insulin. Representative experiments (A–C; the a and b above the top LSNA tracing show where the expanded tracings below were taken.) and group data (D–F) showing that PVN NPY1x (B and E), ArcN insulin (A and D), and PVN NPY1x followed by ArcN insulin (C and F) similarly increased LSNA (bottom). While ArcN insulin did not alter mean arterial pressure (MAP) or heart rate (HR; D), PVN NPY1x followed by ArcN insulin (F) increased AP and HR similarly to PVN NPY1x followed by ArcN artificial cerebrospinal fluid (aCSF) (E). G: illustration of PVN and ArcN injection sites. *P < 0.05 compared with control (CON) values. No between-group differences were observed.