We study the effect of the truncal vagotomy on the degranulation activity of mast cell population in the submucosa of the rumen and fundus of the stomach of the rat after 7, 30, 60, 90 and 120 days of the surgical procedure. Also we analyze if the observed variations are connected with the existence or not of secretory activity in the studied area. The degranulation activity decreases in 7 days in the fundic secretory area with statistic significance, but not in the rumen. A significant increase of the degranulation is seen in both areas, after 90 days. We conclude that the effects of the vagotomy on mast cell degranulation in the submucosa of the stomach of rats depend on the presence or not of secretory activity in the studied area and the length of time after the surgical procedure.