NEW ASPECTS OF THE PATHOPHYSIOLOGY AND TREATMENT OF SECRETORY DIARRHEA

This review presents recent findings regarding the physiological and p athophysiological extra- and intracellular mechanisms of secretory dia rrhoea. Putative interventions directed towards counteracting the mech anisms causing fluid loss, especially in relation to the enteric nervo us system, intracellular mediators, and localization of fluid and elec trolyte transport, are discussed. The enteric nervous system regulates the complex process of transmural fluid and electrolyte transport by controlling the function of the mucosa, the motility, and the microcir culation in both health and disease. Most of the processes, leading to secretory diarrhoea, involve activation of the enteric nervous system , with local release of neurotransmitters and other endogenous effecte rs, which induce chloride secretion. A new therapeutic approach is bas ed on stimulation of absorption and inhibition of secretion by using r eceptor agonists and antagonist, and modulators of intracellular signa l transduction. A physio-pharmacological review of serotonin and the a ntisecretory factor as modulators of intestinal fluid and electrolyte transport is given.