Electroacupuncture activates enteric glial cells and protects the gut barrier in hemorrhaged rats.

AIM: To investigate whether electroacupuncture ST36 activates enteric glial cells, and alleviates gut inflammation and barrier dysfunction following hemorrhagic shock. METHODS: Sprague-Dawley rats were subjected to approximately 45% total blood loss and randomly divided into seven groups: (1) sham: cannulation, but no hemorrhage; (2) subjected to hemorrhagic shock (HS); (3) electroacupuncture (EA) ST36 after hemorrhage; (4) vagotomy (VGX)/EA: VGX before hemorrhage, then EA ST36; (5) VGX: VGX before hemorrhage; (6) α-bungarotoxin (BGT)/EA: intraperitoneal injection of α-BGT before hemorrhage, then EA ST36; and (7) α-BGT group: α-BGT injection before hemorrhage. Morphological changes in enteric glial cells (EGCs) were observed by immunofluorescence, and glial fibrillary acidic protein (GFAP; a protein marker of enteric glial activation) was evaluated using reverse transcriptase polymerase chain reaction and western blot analysis. Intestinal cytokine levels, gut permeability to 4-kDa fluorescein isothiocyanate (FITC)-dextran, and the expression and distribution of tight junction protein zona occludens (ZO)-1 were also determined. RESULTS: EGCs were distorted following hemorrhage and showed morphological abnormalities. EA ST36 attenuated the morphological changes in EGCs at 6 h, as compared with the VGX, α-BGT and HS groups. EA ST36 increased GFAP expression to a greater degree than in the other groups. EA ST36 decreased intestinal permeability to FITC-dextran (760.5 ± 96.43 ng/mL vs 2466.7 ± 131.60 ng/mL, P < 0.05) and preserved ZO-1 protein expression and localization at 6 h after hemorrhage compared with the HS group. However, abdominal VGX and α-BGT treatment weakened or eliminated the effects of EA ST36. EA ST36 reduced tumor necrosis factor-α levels in intestinal homogenates after blood loss, while vagotomy or intraperitoneal injection of α-BGT before EA ST36 abolished its anti-inflammatory effects. CONCLUSION: EA ST36 attenuates hemorrhage-induced intestinal inflammatory insult, and protects the intestinal barrier integrity, partly via activation of EGCs.

Electroacupuncture ST36 prevents postoperative intra-abdominal adhesions formation.

BACKGROUND: We have recently proved electroacupuncture (EA) ST36 exerted an anti-inflammatory effect in the early phase of intra-abdominal adhesion formation. Evidences indicate that the anti-inflammatory effect of EA ST36 involves a cholinergic anti-inflammatory pathway-dependent mechanism via the vagus nerve. However, the exact effects and accurate vagal modulation of acupuncture in prevention of postoperative intra-abdominal adhesion formation has not been thoroughly evaluated. MATERIALS AND METHODS: Sprague-Dawley rats subjected to abdominal adhesion lesions operation at the cecum and abdominal wall were randomly divided into six groups as follows: (a) EAN: EA non-channel acupoints; (b) EA: EA ST36 after abdominal lesions; (c) VGX/EA: vagotomy (VGX) after abdominal lesions, then EA ST36; (d) VGX/EAN: VGX after abdominal lesions, then EAN; (e) α-BGT/EA: intraperitoneal injection of α-bungarotoxin (α-BGT, an antagonist of α7 subunit of cholinergic nicotinic receptor) before EA ST36, and (f) α-BGT/EAN group: α-BGT injection before EAN. Seven days after abdominal surgical lesions, the levels of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) in the adhesive tissue were evaluated, macroscopic observation and histopathologic evaluation of adhesion formation and assessment of angiogenesis by immunohistochemical staining of platelet endothelial cell adhesion molecule-1 (CD31) were performed. RESULTS: EA ST36 reduced TNF-α and VEGF levels in adhesive tissue homogenates 7 d after surgery, whereas vagotomy or intraperitoneal injection of α-BGT before EA ST36 reversed its suppressive effects. EA at non-channel acupoints with or without vagotomy or intraperitoneal injection of α-BGT before EA had no suppressive effects on TNF-α and VEGF levels. EA ST36 alleviated the adhesion formation, with both of macroscopic and histopathologic adhesion scores significantly lower than those of the EAN group (1.56 ± 0.29 versus 3.00 ± 0.82, 1.35 ± 0.4 versus 3.91 ± 0.8, respectively, both P < 0.05). Compared with the EAN group, EA ST36 significantly decreased angiogenesis evidenced by reduced CD31 positive microvessel density in adhesive tissue. CONCLUSIONS: EA ST36 might reduce the postoperative local inflammatory response, attenuate the angiogenesis, and alleviate the adhesion formation partly via activating the cholinergic anti-inflammatory mechanism.

Electroacupuncture at Zusanli (ST36) promotes gastric emptying and mucosal blood flow during oral resuscitation of scalded rats with a pyruvate-enriched ORS.

AIM: The aim of this study was to investigate the effect of electroacupuncture at ST36 (EA ST36) on gastric emptying and mucosal blood flow during intragastric resuscitation with pyruvate-enriched oral rehydration solution (Pyr-ORS) in scalded rats. METHODS: The rats were subjected to a 35% total body surface area (TBSA) of scald injury and randomly divided into five groups (N=24) and two subgroups (n=12) in each group. The Pyr-ORS was delivered intragastrically according to the Parkland formula immediately after scalding at a dose of 1 mL kg(-1) %TBSA(-1) in 1 h. In these animals, the bilateral Zusanli points (ST36) were electroacupunctured at a constant voltage (2 mA and 2-100 HZ) for 0.5 h immediately after intragastric resuscitation. At 2 and 4 h after scalding, the gastric emptying rate (GER) and gastric mucosal blood flow (GMBF) were determined, and the motilin levels of the plasma and gastric tissues were also analyzed at two time points, respectively. RESULTS: GER and GMBF were markedly decreased in groups with scalding and resuscitation, compared with the sham groups at two time points (P<0.05), but they were greatly improved in groups byEAST36 at 2 and 4 h after sustaining scald injuries (P<0.05). Bilateral vagotomy further aggravated the reduction of GER and GMBF in scalded rats. EA after gastric vagotomy failed to raise GER and GMBF. Neither EA nor vagotomy had effects on the reduced motilin levels of plasma and gastric tissues in animals after scalding. CONCLUSION: EA ST36 has a significant effect on improving gastric emptying and mucosal ischemia in the oral resuscitation of burn injury, possibly through the activation of a cholinergic nerve-dependent mechanism. In addition, EA ST36 showed no effects on motilin levels, but requires further investigations.