Synchronized dual pulse gastric electrical stimulation improves gastric emptying and activates enteric glial cells via upregulation of GFAP and S100B with different courses of subdiaphragmatic vagotomy in rats

Abstract

Previous research and clinical practice have indicated that damage to the vagal nerve may seriously affect gastrointestinal physiological movement behavior. The aim of the current study was to observe the change of gastric motility, as well as enteric glial cells (EGCs) in the stomach with different courses of vagal nerve transection in rats prior to and following synchronized dual pulse gastric electrical stimulation. The gastric emptying rates were measured to assess the gastric motility. The glial markers, containing calcium binding protein (S100B) and glial fibrillary acidic protein (GFAP), were detected by reverse transcription‑quantitative polymerase chain reaction and double‑labeling immunofluorescence analysis. Ultrastructural changes of EGCs were observed using transmission electron microscopy. Gastric emptying was delayed in the terminal vagotomy group, compared with the terminal control group. The effect of long‑term synchronized dual pulse gastric electrical stimulation (SGES) was superior to short‑term SGES in terminal groups. The expression levels of S100B/GFAP were markedly decreased in the terminal vagotomy group compared with the terminal control group. Following short‑term or long‑term SGES, S100B/GFAP gene and protein expression increased in terminal groups. However, long‑term SGES was more effective than short‑term SGES and the difference was statistically significant. Vagal nerve damage leads to gastric motility disorder and weakens the function of EGCs. Therefore, SGES may improve stomach movement behavior and restore the impaired EGCs. The underlying mechanism of the effect remains elusive, but maybe associated with activation of EGCs.

A Novel Approach in Spinal Cord Stimulation for Enhancing Gastric Motility: A Preliminary Study on Canines

“…[20][21][22] In addition, another cannula was placed in the duodenum (10 cm below the pylorus for the assessment of gastric emptying. [23][24][25][26] Immediately after the surgery, antibiotics (cefpodoxime, 10 mg/kg) and pain medications (buprenorphine SR, 0.06 mg/kg) were given for a period of 7 days and 3 days, respectively. The animals were monitored twice daily for a period of at least 2 weeks and no experiments were performed before the dogs were completely recovered from the surgical proce-dures.…”

Gastric electrical stimulation improves enteric neuronal survival

“…In the present study, we demonstrated that SGES with a long pulse (300 msec, 4 mA) followed by 5 short pulses (0.3 msec, 100 Hz, 4 mA) markedly upregulated GDNF expression together with p-Akt and PGP9.5, and reduced the number of TUNEL-positive cells. Our previous studies demonstrated that SGES activated EGCs and improved gastric emptying (31,32). This result indicates that SGES restores injured ENS and improves gastric motility.…”

“…Our data indicated that Cx43 expression was markedly reduced in the vagotomized groups and that short- or long-term SGES increased Cx43 expression. Our previous study found that SGES improved gastric emptying in vagotomized rats through the activation of enteric glial cells (32). More research is required to determine whether SGES enhances the cross-talk between enteric glial cells via the Cx43 protein and further promotes the release of GDNF.…”