Quantification of the sulphomucin-producing cell population of the colonic mucosa during protracted stress in rats.

The sulphomucins contained in goblet cells of the descending colon of 55 Sprague-Dawley rats were histochemically labelled by High Iron Diamine (HID) and quantified in an image analyzer (Cortex controller). After transportation to the stress laboratory, 25 rats were compelled to swim for two consecutive hours/day either only once (5 rats), for one week (5 rats), two weeks (5 rats), four weeks (5 rats) or eight weeks (5 rats). 25 additional rats were only transported to the stress laboratory (i.e. "sham-handled" control), either once (5 rats), for one week (5 rats), two weeks (5 rats), four weeks (5 rats) or eight weeks (5 rats). The remaining 5 rats were "untransported", resting control rats (i.e. day zero). The results were expressed in percent of HID-staining/total mucosa analyzed. When various time intervals were compared with those of day zero (i.e. horizontal study), it was found that one day swimming rats had a significantly lower percentage (p less than 0.001) of HID stained material. The fluctuations at other time intervals were non-significant. On the other hand, for transported rats, a significant increase (p less than 0.001) in the percentage of HID positive areas was found for rats swimming for eight weeks. When compared to day one, the percentage of HID positive areas increased from day one to one-eight weeks, the differences being significant (p less than 0.001) at four and (p less than 0.01) eight weeks. Similar results were found for transported rats.(ABSTRACT TRUNCATED AT 250 WORDS)