Objective: To observe the dynamic distribution of the extravasated Evans Blue (EB) dye points (neurogenic inflammatory response) at the skin after acute gastric mucosal injury (AGMI) and its relation to the related regular acupoints in the locations in rats.
Methods: A total of 70 Wistar rats were randomized into normal control (n=10), normal saline (n=10), and AGMI (n=50) groups. The AGMI group was further divided into 5 h, 2 d, 3 d, 4 d and 5 d subgroups with 10 rats in each. AGMI model was duplicated by intragastric perfusion of diluted hydrochloric acid (HCl, 0.5 mol/L). Evans Blue Dye (50 mg/kg, 50 mg/mL in 0.9% saline) was given to the rats before AGMI modeling. The plasma extravasated EB points at the skin of the whole body were observed after removal of the hair.
Results: The extravasated EB points presented a nerve-segmental distribution, with the proportion of the points in the location being 47.5% for "Geshu" (BL 17),58. 82% for "Jizhong" (GV 6), 88.23% for "Pishu" (BL 20), 82.35% for "Weishu" (BL21), 17.64% for "Zhongwan" (CV 12), and 5.88% for "Shangwan" (CV 13), respectively. The plasma extravasation of EB seldom appeared in normal rats and only fewer points were found in rats accepted administration of 0.9% saline. Significant differences were found between model and normal control groups, and between model and normal saline groups in the numbers of the extravasated EB points (P < 0.01, P < 0.05). The number of the extravasated EB points was related to the phase of gastric mucosa injury, being most on the 2nd and 3rd day after modeling and disappearing gradually along with the natural repair of AGMI.
Conclusion: AGMI promotes the plasma extravasation of EB and the extravasated EB points present a nerve-segmental distribution and have a higher corresponding rate with some acupoints including "Pishu" (BL 20), "Weishu" (BL 21), etc., suggesting an activation of the normally silent acupoints under diseased conditions.