Fundamentals of neurogastroenterology (original) (raw)

Neuropathophysiology of functional gastrointestinal disorders

World journal of gastroenterology : WJG, 2007

The investigative evidence and emerging concepts in neurogastroenterology implicate dysfunctions at the levels of the enteric and central nervous systems as underlying causes of the prominent symptoms of many of the functional gastrointestinal disorders. Neurogastroenterological research aims for improved understanding of the physiology and pathophysiology of the digestive subsystems from which the arrays of functional symptoms emerge. The key subsystems for defecation-related symptoms and visceral hyper-sensitivity are the intestinal secretory glands, the musculature and the nervous system that controls and integrates their activity. Abdominal pain and discomfort arising from these systems adds the dimension of sensory neurophysiology. This review details current concepts for the underlying pathophysiology in terms of the physiology of intestinal secretion, motility, nervous control, sensing function, immuno-neural communication and the brain-gut axis.

Fundamentals of Neurogastroenterology: Physiology/Motility - Sensation

Gastroenterology, 2016

The fundamental gastrointestinal functions include motility, sensation, absorption, secretion, digestion and intestinal barrier function. Digestion of food and absorption of nutrients normally occurs without conscious perception. Symptoms of functional gastrointestinal disorders are often triggered by meal intake suggesting abnormalities in the physiological processes are involved in the generation of symptoms. In this manuscript, normal physiology and pathophysiology of gastrointestinal function, and the processes underlying symptom generation are critically reviewed. The functions of each anatomical region of the digestive tract are summarized. The pathophysiology of perception, motility, mucosal barrier, and secretion in functional gastrointestinal disorders as well as effects of food, meal intake and microbiota on gastrointestinal motility and sensation are discussed. Genetic mechanisms associated with visceral pain and motor functions in health and functional gastrointestinal d...

The nervous system and gastrointestinal function

Developmental Disabilities Research Reviews, 2008

The enteric nervous system is an integrative brain with collection of neurons in the gastrointestinal tract which is capable of functioning independently of the central nervous system (CNS). The enteric nervous system modulates motility, secretions, microcirculation, immune and inflammatory responses of the gastrointestinal tract. Dysphagia, feeding intolerance, gastroesophageal reflux, abdominal pain, and constipation are few of the medical problems frequently encountered in children with developmental disabilities. Alteration in bowel motility have been described in most of these disorders and can results from a primary defect in the enteric neurons or central modulation. The development and physiology of the enteric nervous system is discussed along with the basic mechanisms involved in controlling various functions of the gastrointestinal tract. The intestinal motility, neurogastric reflexes, and brain perception of visceral hyperalgesia are also discussed. This will help better understand the pathophysiology of these disorders in children with developmental disabilities.

Central nervous system involvement in functional gastrointestinal disorders

Best Practice & Research Clinical Gastroenterology, 2004

Although functional gastrointestinal disorders (FGID) are common, their pathophysiology remains incompletely understood. It is generally accepted that dysfunction of the bidirectional pathways between the gastrointestinal tract and the central nervous system (the 'brain -gut axis') at any level can cause FGID symptoms. In this review article, we focus on the role of the central nervous system in the brain -gut axis.

Fundamentals of Neurogastroenterology: Basic Science

Gastroenterology, 2006

Vagal and spinal afferent nerve fibers transmit sensory information from the GI tract to the CNS. Vagal afferents have cell bodies in nodose ganglia and enter the Abbreviations used in this paper:

Applied Principles of Neurogastroenterology: Physiology/Motility Sensation

Gastroenterology, 2006

Many of the signs distinguished within the functional gastrointestinal problems (FGIDs) are consistent with dysfunction of the sensory and/or motor apparatus of thedigestive tract. Assessment of those phenomena in mancan be undertaken by utilizing a broad variety of invasiveand noninvasive methods, some nicely established andothers requiring further validation. By utilizing such strategies, alterations in each sensory and motor performhave been reported within the FGIDs; numerous mixturesof such dysfunction happen in several regions of thedigestive tract within the FGIDs. Our understanding of theorigins of this intestine sensorimotor dysfunction is steadilyrising. Thus, inflammatory, immunologic, and otherprocesses, in addition to psychosocial components similar tostress, can alter the traditional patterns of sensitivity andmotility by way of alterations in native reflex exercise or by way ofaltered neural processing along the brain-gut axis. In this context, a potential function of genetic factors, early-lifeinfluences, enteric flora, dietary elements, and autonomic dysfunction also must be considered within thedisease model. A firm relationship between sensorimotor dysfunction and the manufacturing of signs, nevertheless, has been troublesome to show, and so the medicalrelevance of the former requires continuing exploration. Based on the conceptual framework established to date,numerous suggestions for further progress canbe made.The digestive tract is fitted with a complex wiringsystem that modulates its response to the innerand external environment. The 2 aspects of gut physiology most relevant to the functional gastrointestinal disorders (FGIDs) are sensation and motility. In well being,physiological stimuli from the gut induce motor reflexes,but these remain largely unperceived, with the exceptionof these associated to ingestion and excretion. Visceral afferent pathways, nonetheless, also function an "alarm" systemto induce acutely aware notion when applicable. Gutmotility, encompassing myoelectrical exercise, phasiccontractions, tone, compliance, accommodation, andtransit, is regulated by reflex mechanisms and is intimately related to gut sensitivity.

Enteric Nervous System: A Review

2015

Enteric nervous system directs and regulates the breakdown, absorption and elimination of food in our digestive system. However, alongside its digestive functions, enteric nervous system has also gained importance because of the discovery of its bidirectional link with intestinal flora, which has recently started to be considered as a separate organ in addiction to its digestive functions. Enteric nervous system contains approximately 100 million nerve cells, operates both independently and in coordination with the central nervous system, interacts with many neurotransmitters and is related to many conditions and structures such as the intestinal flora, mood, immune system and the efficiency of food utilization. It has a clinical importance on account of the diseases it is associated with. Recent studies focus on the connections between the intestinal flora, enteric nervous system and mechanisms of disease development. In order to understand these studies and pathological mechanisms...

Principles of applied neurogastroenterology: physiology/motility–sensation

Gut, 1999

Many of the symptoms characteristic of the functional gastrointestinal disorders (FGID) are consistent with dysfunction of the motor and/or sensory apparatus of the digestive tract. Those aspects of sensorimotor dysfunction most relevant to the FGID include alterations in: gut contractile activity; myoelectrical activity; tone and compliance; and transit, as well as an enhanced sensitivity to distension, in each region of the gastrointestinal tract. Assessment of these phenomena involves a number of techniques, some well established and others requiring further validation. Using such techniques, researchers have reported a wide range of alterations in sensory and in motor function in the FGID. Importantly, however, relationships between such dysfunction and symptoms have been relatively weak, and so the clinical relevance of the former remains unclear. Moreover, the proportions of patients in the various symptom subgroups who display dysfunction, and the extent and severity of their symptoms, require better characterization. On a positive note, progress is occurring on several fronts, especially in relation to functional dyspepsia and irritable bowel syndrome, and based on the data gathered to date, a number of areas where further advances are required can be highlighted.