ABSTRACT
Objective To observe the effect of a rotating magnetic field in preventing and treating irradiation-induced esophagitis in rats. Methods Forty female Wistar rats were randomized into 5 groups:a non-irradiated control group,an irradiation group,an amifostine treatment group ( amifostine group ),a 90 min magnetic field treatment group (90 min magnetic group) and a 120 min magnetic field treatment group ( 120 min magnetic group),with 8 rats in each group.The esophaguses of all rats except those in the control group were exposed to a single irradiation with 6 MV X-rays from a linear accelerator at a dosage of 43 Gy.Four rats in each group were randomly chosen to be observed 1 and 2 weeks after the irradiation.Blood cytokines were detected in their arterial blood.Any pathological changes of the esophagus were observed with HE staining under a light microscope at the same time. Results Irradiation-induced esophagitis was observed in the irradiation group 7 days after irradiation,with obvious exfoliation and necrosis of the esophagal epithelium mucosae.The submucosa were hyperaemic and dropsical with abundant inflammatory cell infiltration.The pathological changes of the esophagus were similar at 7 and 14 days after irradiation.However,the irradiation-induced esophagitis of rats in the amifostine group,the 90 min magnetic group and the 120 min magnetic group were relatively slighter and the blood leucocytes and neutrophis in those 3 groups were significantly lower than those in the irradiation group,while a tendency toward repair of the mucosa of the esophagus was detected.Serum TNF-α,IL-1 and IL-6 in the 90 min magnetic group and 120 min magnetic group were significantly lower than those in the irradiation group. Conclusions Both a rotating magnetic field and amifostine can help prevent and treat irradiation-induced esophagitis.Their therapeutic efficacy is similar.Exposure to a rotating magnetic field could inhibit the expression of inflammatory factors,and thus lessen the inflammatory reaction of acute irradiation-induced esophagitis.