Microcirculatory and trophic effects of short chain fatty acids in the human rectum after Hartmann's procedure.

Short chain fatty acids (acetic, propionic and butyric) were instilled into the rectum of patients who had undergone Hartmann's procedure. The following parameters were examined before and after a 2-week treatment period with short chain fatty acids (100 ml twice daily at a total concentration of 150 mM): (1) microcirculatory effects in vivo using a laser Doppler flow technique, and (2) morphometrical changes in mucosal biopsies. The following parameters were significantly increased in all patients after treatment: (1) mucosal blood flow, (2) the fractional crypt cell epithelium plus surface epithelium volume in relation to total tissue volume down to the muscularis mucosa, (3) nuclear volume in the crypt and the surface epithelium, and (4) the fractional nuclear volume to total cell volume in the crypt and the surface epithelium. These data suggest that short chain fatty acids in the human colon have trophic and vasodilatory effects.