FIG. 4.
Hypothalamic KATP channel inhibition and hepatic branch vagotomy significantly reduce resveratrol action. A: Representative schematic of the sagittal section of the brain at the level of the arcuate nucleus. KATP channels in the arcuate nucleus have a role in regulating glucose production. Neural activity from the arcuate nucleus is transferred to the nucleus of solitary tract/dorsal motor vagal nucleus of the brain stem and subsequently relayed to the liver via the vagus nerve. B: Experimental protocol for resveratrol-glibenclamide studies. C–F: Central glibenclamide significantly attenuated the effect of resveratrol on hepatic glucose production. G and H: Timeline and basal insulin clamp protocol for hepatic vagotomy and sham studies. I–L: Effect of hepatic vagotomy or sham operation on GIR, glucose production, and glucose uptake after resveratrol treatment. For all studies n = 4–6 per group. All values are mean ± SEM. *P < 0.05, **P < 0.005 compared with control. ARC, arcuate nucleus; KATP, potassium sensitive ATP channel; NTS, nucleus of solitary tract; DMX, dorsal motor vagal nucleus; SHAM, sham-operated; HVG, hepatic vagotomy. For all studies: control, white bars; resveratrol, black bars; resveratrol and glibenclamide, striped bars; glibenclamide only, hatched bars.