The effects of severe zinc deficiency on intestinal permeability: an ultrastructural study.

Evidence suggests that intestinal transport of water and electrolytes may be altered in zinc deficiency. We examined the structural features of intestinal epithelial cells of zinc-deficient rats using electron microscopy and assessed the integrity of the junctional complexes using a heavy metal tracer, lanthanum hydroxide. The absorptive cells, as well as Paneth cells and chromaffin cells, were not found to have ultrastructural changes of a consistent nature in zinc deficiency. Moreover, the integrity of the junctional complexes was found to be preserved. These findings suggest that the abnormalities in intestinal transport previously reported are not secondary to increased tight junction permeability in zinc deficiency.