The Enteric Nervous System

Chapter 1: Structure of the enteric nervous system. The enteric plexuses. Interconnections between the plexuses. Extent of the ganglionated plexuses. Intramural extensions of extrinsic nerves. Electron microscope studies. Enteric glia. The structural similarities and functional differences between regions may have an evolutionary basis. Development of the enteric nervous system. Maturation of enteric neurons and development of function. Changes in enteric neurons with aging. Summary and conclusions. Chapter 2: Constituent neurons of the enteric nervous system. Shapes of enteric neurons. Cell physiological classifications of enteric neurons. Functionally defined enteric neurons. Neurons in human intestine with equivalence to those investigated in laboratory animals. Summary and conclusions. Chapter 3: Reflex circuitry of the enteric nervous system. Evolution of ideas about enteric circuitry. Motility controlling circuits of the small and large intestine. Intrinsic secretomotor and vasomotor circuits. Assemblies of neurons. Circuits in the esophagus and stomach. Co-ordination of motility, secretomotor and vasomotor reflexes. Circuits connecting the intestine, biliary system and pancreas. Sympathetic innervation of the gastrointestinal tract. Summary and conclusions. Chapter 4: Pharmacology of transmission and sites of drug action in the enteric nervous system. Chemical coding and multiple transmitters. Transmitters of motor neurons that innervate the smooth muscle of the gut. Transmitters at neuro-neuronal synapses. Sites within the reflex circuitry where specific pharmacologies of transmission can be deduced to occur. Transmission from entero-endocrine cells to IPANs. Roles of interstitial cells of Cajal in neuromuscular transmission. Transmitters of secretomotor and vasodilator neurons. Synapses in secretomotor and vasodilator pathways. Transmitters of motor neurons innervating gastrin cells. Summary and conclusions. Chapter 5: Neural control of motility. Rhythmic activity of gastrointestinal muscle. Structure and properties of interstitial cells of Cajal. Relationship between slow wave activity and neural control. Gastric motility. Patterns of small intestine motility and their intrinsic neural control. Motility of the colon. Neural control of the esophagus. Gall-bladder motility. Sphincters. Muscle of the mucosa. Mechanism of sympathetic inhibition of motility in non-sphincter regions. Sympathetic innervation of the sphincters. Physiological effects of noradrenergic neurons on motility in undisturbed animals. Reflex activities of sympathetic neurons that affect motility. Summary and conclusions. Chapter 6: Enteric neurons and the physiological control of fluid secretion and vasodilation. Water and electrolyte secretion in the small and large intestines. Reflex control of water and electrolyte secretion. Secretion of gastric acid. Pepsinogen secretion. Gastric secretion of bicarbonate. Secretion into the gall bladder. Pancreatic exocrine secretion. Summary and conclusions. Chapter 7: Disorders of motility and secretion and therapeutic targets in the enteric nervous system. Therapeutic endpoints for motility disorders. Therapies for secretory diarrheas. Enteric neuropathies involving neuronal loss or phenotypic changes. Mitochondriopathies with intestinal manifestations. Irritable bowel syndrome and plasticity of enteric neurons. Summary and conclusions. Epilogue: the future of enteric neurobiology. References. Index.