Electroacupuncture in rats infected with Strongyloides venezuelensis: effects on gastrointestinal transit and parasitological measurements.

OBJECTIVE: To investigate the effects of electroacupuncture (EA) at ST36 and CV12 on gastrointestinal transit and parasitological measurements during Strongyloides venezuelensis infection in rats. DESIGN: Rats were infected with S. venezuelensis and allocated to one of three groups that were infected and remained untreated (SV group, n=8), infected and treated with EA at CV12 (SV+CV12 group, n=8) or infected and treated with EA at ST36 (SV+ST36 group, n=8). EA was performed every 3 days over a 21-day period, at 4 mA intensity and 15 Hz frequency for 20 min. At 2 and 20 days post-infection (dpi), body weight, food and water intake, and faecal characteristics were monitored over a 24-hour period. Gastric emptying, caecal arrival time, small intestinal transit and eggs per gram (EPG) of faeces were calculated at 3, 9, 15 and 21 dpi. At 21 dpi, intestinal worm recovery was counted. RESULTS: EA at ST36 and CV12 slowed gastric emptying over the course of infection time. An accelerated intestinal transit was observed in the ST36 group, and after CV12 treatment the same effect was observed at 9 and 15 dpi. At 9 dpi, EPG was increased in the CV12 group. ST36 treatment decreased EPG at 9 and 15 dpi. At 21 dpi, both the ST36 and CV12 groups had increased EPG and worm numbers. No changes were observed in the other parameters analysed. CONCLUSIONS: EA at ST36 and CV12 provoked changes in gastrointestinal transit that may be beneficial to the host during S. venezuelensis infection; however, based on the number of worms and EPG at 21 dpi, the indication for EA in the treatment of strongyloidiasis needs to be carefully assessed.

Gastrointestinal Motility, Mucosal Mast Cell, and Intestinal Histology in Rats: Effect of Prednisone.

Our aim was to verify the effects of prednisone related to gastrointestinal motility, intestinal histology, and mucosal mast cells in rats. Two-month-old male Wistar rats were randomly assigned to control group (vehicle) animals receiving saline 0.9% (n = 7) or treated orally with 0.625 mg/kg/day of prednisone (n = 7) or 2.5 mg/kg/day of prednisone (n = 7) during 15 days. Mast cells and other histologic analyses were performed in order to correlate to gastric emptying, cecum arrival, and small intestine transit evaluated by Alternating Current Biosusceptometry. Results showed that prednisone in adult rats increased the frequency of gastric contractions, hastened gastric emptying, slowed small intestinal transit, and reduced mucosal mast cells. Histologically, the treatment with both doses of prednisone decreased villus height, whereas longitudinal and circular muscles and crypt depth were not affected. These findings indicate an impairment of intestinal absorption which may be linked to several GI dysfunctions and symptoms. The relationship between gastrointestinal motor disorders and cellular immunity needs to be clarified in experimental studies since prednisone is one of the most prescribed glucocorticoids worldwide.