Fig. 6.

Surgical transection and chemical inhibition of extrinsic vagal gut neuronal communication has no effect on intestinal MTP. Panels A–D: Hepatic and celiac vagotomies in male C57BL6/J mice were performed as previously described (48). Mice were allowed to recover for 2 weeks and fasted overnight before euthanizing. Intestinal and hepatic tissues from hepatic vagotomy (HV, n = 13), celiac vagotomy (CV, n = 9), hepatic and celiac double vagotomy (HCV, n = 7), and sham (Sham, n = 21) operated mice were used for MTP activity assays (Panels A and C). RNA was used to measure in triplicate MTP (Panels B and D), and ARPp0 mRNA. The ratio between gene of interest and ARPp0 in sham mice was used to normalize mRNA levels in all samples. Panels E–H: Male C57BL6/J mice (5 per group) were injected intraperitoneally with atropine methyl nitrate (10 mg/kg). After 3 h of fasting, intestinal and liver samples were used to measure MTP activity (Panels E and G, respectively) and mRNA levels (Panels F and H, respectively). Values are mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.001 compared with Sham. HCV, hepatic and celiac vagotomy; HV, hepatic vagotomy; MTP, microsomal triglyceride transfer protein.