Gastrointestinal and Autonomic Complications of Diabetes Mellitus

Gastrointestinal (GI) function is controlled by the extrinsic and intrinsic nervous systems. Extrinsic neural control is exerted by the parasympathetic and sympathetic nervous components of the autonomic nervous system. Intrinsic control is imposed by the enteric plexuses (the “little brain” in the digestive tract) (Fig. 1). Experimental models of gut motor function suggest a predominant modulatory role for the extrinsic nervous system, and primary control through the (intrinsic) enteric nervous system (1). Thus, derangements of the extrinsic nerves at any level may result in alteration of GI motility and secretion (2).