Melanosis coli: Studies of the toxic effects of irritant purgatives

Abstract

Colonic biopsies from six patients with normal colons and seven patients with melanosis coli were studied ultrastructurally and histochemically for lysosomal enzymes. Anthraquinone purgatives were found to increase the number of macrophages in the connective tissue of the colonic mucosa. In addition, they cause an increase in the intensity of lysosomal activity and an increase in the number of lysosomes in macrophages, Schwann cells and neurones of the submucosal plexus of the colonic mucosa.