Several studies showed muscularis macrophages (MMφ) are associated with GI motility disorders. The purpose of this study was to preliminary explore the association between MMφ and achalasia.
Tissue samples of the lower esophageal sphincter (LES) high-pressure zone were obtained from 27 achalasia patients and 10 controls. Immunohistochemistry for MMφ, interstitial cells of Cajal (ICC), neuronal nitric oxide synthase (nNOS), and glial cells were conducted. Histological characteristics were compared between groups, and correlation analysis was performed.
Fewer ICC was found in achalasia compared with controls (P = 0.018), and the level of M1 macrophages was higher than that in controls no matter in terms of the number or the proportion of M1(P = 0.026 for M1 and 0.037 for M1/MMφ). Statistical differences were found between two groups in terms of proportion of M2 and ratio of M1 to M2 (P = 0.048 for M2/ MMφ and < 0.001 for M1/M2). For the correlation analysis, significant correlations were detected between levels of nNOS, ICC, and glial cells in patients with achalasia (P = 0.026 for nNOS and ICC, 0.001 for nNOS and glial cells, 0.019 for ICC and glial cells). There were significant correlations between M2/MMφ and levels of ICC (P = 0.019), glial cells (P = 0.004), and nNOS (P = 0.135).
Patients with achalasia had a higher level of M1/M2 ratio in LES and significant correlations were found between M2/MMφ and numbers of ICC and glial cells, which suggested that MMφ were probably associated with occurrence and development of achalasia.

OBJECTIVE: To observe the effects of electroacupuncture (EA) on gastrointestinal motility and the ultrastructure of interstitial cells of Cajal (ICC) and the expressions of c-kit receptor protein and stem cell factor (SCF) mRNA in diabetic gastroparesis (DGP) rats, so as to explore its mechanism.
METHODS: Fifty SD rats were randomly divided into normal, model, acupoint, non-acupoint and metoclopramide groups (n＝10 rats/group). DGP model was established by intraperitoneal injection of streptozotocin (STZ, 2%), and raised with high-sugar high-fat diet irregularly. EA (sparse-dense, 10 Hz/50 Hz, 2 mA, 20 min) was applied at \"Zusanli\" (ST 36), \"Liangmen\" (ST 21) and \"Sanyinjiao\" (SP 6), and the corresponding non-acupoints of the 3 acupoints, daily for 15 days. The rats in metoclopramide group received intragastric administration of metoclopramide (1.7%, 1 mL/100 g) for 15 days, once a day. Blood sugar was determined with One Touch blood glucose test paper. The gastric emptying rate (GER) and the intestinal propulsion rate (IPR) were measured by intragastric phenol red. The ultrastructure of ICC was detected by transmission electron microscopy. The expression levels of c-kit receptor protein and SCF mRNA of gastric antrum were examined respectively by Western blot and RT-PCR.
RESULTS: Compared with the normal group, the blood glucose significantly increased in the model group (P<0.01), while the GER, IRP and the expression level of SCF mRNA in the gastric antrum significantly decreased (P<0.01), and the ultrastructure of ICC appeared apoptosis-like changes. The blood glucose of the EA group was obviously decreased compared with that of the model group (P<0.05); the GER and IRP significantly increased(P<0.05, P<0.01); the expression level of SCF mRNA increased (P<0.01), the number of ICC increased and its ultrastructure was repaired. There was some relief on ICC ultrastructure in the acupoint group compared with that in the non-acupoint group; and SCF mRNA increased (P<0.05). There was no significant difference on c-kit receptor expression among all the modeling groups (P＞0.05).
CONCLUSIONS: EA at ST 36, etc. can regulate the blood glucose and improve gastrointestinal emptying in DGP rats. The mechanism may be related to up-regulating SCF mRNA, repairing ICC ultrastructure, restoring the pacing function, and improving gastrointestinal motility.