Impact Of Oesophageal Afferent Processing On Regulatory And Protective Reflexes, And Perception Of Symptoms
Funder
National Health and Medical Research Council
Funding Amount
$247,500.00
Summary
Symptoms of acid reflux, heartburn and regurgitation, are extremely common, occurring weekly in 20% of the population. Curiously, about 1-4 of people with heartburn don't have any more acid exposing their oesophagus than do normal people. We do not understand this apparent increased sensitivity. Many patients with reflux present with cough, asthma, hoarseness, sore throat or even lung fibrosis. Regurgitation of acid causes some of these conditions. It is estimated that 60% of adult asthmatics ha ....Symptoms of acid reflux, heartburn and regurgitation, are extremely common, occurring weekly in 20% of the population. Curiously, about 1-4 of people with heartburn don't have any more acid exposing their oesophagus than do normal people. We do not understand this apparent increased sensitivity. Many patients with reflux present with cough, asthma, hoarseness, sore throat or even lung fibrosis. Regurgitation of acid causes some of these conditions. It is estimated that 60% of adult asthmatics have reflux for example. The purpose of this research is to examine the notion that the sensory nerves coming from the oesophagus are somehow tuned up to fire off too readily. If true this phenomenon may well underlie the inappropriate relaxation of the oesophageal valve mechanisms that normally prevent acid flowing up into the throat and into the airways. Additionally it may explain why so many sufferers seem to be hypersensitive to even small amounts of acid. These studies will better define the nerve pathways involved in heartburn and regurgitation and help us target these diseases with specific drugs in the future.Read moreRead less
Spatio-temporal Analysis Of Rat Intestinal Motility In Physiological And Disease Models
Funder
National Health and Medical Research Council
Funding Amount
$358,750.00
Summary
This project addresses the question of how the movements of the gut are controlled in health and disease. The progress of food along the gut is due to movements of the involuntary muscle of the wall of the intestine. Three fundamental mechanisms are involved. One is the spontaneous ability of the intestinal muscle to contract rhythmically and is driven by a delicate net of pacemaker cells. Fast propulsion of food contents depends on nerve circuits in the gut wall that generate a powerful pumping ....This project addresses the question of how the movements of the gut are controlled in health and disease. The progress of food along the gut is due to movements of the involuntary muscle of the wall of the intestine. Three fundamental mechanisms are involved. One is the spontaneous ability of the intestinal muscle to contract rhythmically and is driven by a delicate net of pacemaker cells. Fast propulsion of food contents depends on nerve circuits in the gut wall that generate a powerful pumping behaviour to prevent over-filling or to eject toxic or irritating substances (eg: some laxatives activate this mechanisms). This is often called peristalsis. A third mechanism consists of activity of nerve cells in the gut, that slowly propagates along the intestine and causes the muscle to contract, sweeping along any remnants. The movements generated by these three mechanisms occur in segments of intestine isolated from rats. The major difficulty up until now has been to relate the actual movements in living animals to these fundamental mechanisms. It is now possible to bridge this gap because we have developed methods to record, display and measure graphically the actual movements. Movements are transformed into spatio-temporal maps which show all of the contractions over a period of time. Coordinated activity is visible in these maps as recognisable patterns or visual objects. Measurements can be readily made with conventional statistics. The literature in gastroenterology is full of descriptions of motility based on indirect methods of recordings. In this project we will be able to correlate the previous indirect methods with the new graphic methods and thus establish a clearer, simpler and more accurate classification of normal patterns of intestinal motility. We will then use this to establish what goes wrong in a number of experimental diseases known to affect adversely the movements of the intestine.Read moreRead less