Mechanisms Of Action Of Neurochemicals And Modulators In Human Intestine: Changes In Disease
Funder
National Health and Medical Research Council
Funding Amount
$442,500.00
Summary
Inflammatory bowel disease (IBD) and idiopathic chronic constipation (ICC) are two serious gastrointestinal disorders, for which no effective medical treatment is known. We will investigate the hypothesis that abnormalities in the nerve chemicals found in the gut contribute to the aetiology of these diseases. Our studies will examine the sites of action (receptors) for these chemicals (neurotensin and acetylcholine) in the small and large intestine. The mechanisms governing motility changes in r ....Inflammatory bowel disease (IBD) and idiopathic chronic constipation (ICC) are two serious gastrointestinal disorders, for which no effective medical treatment is known. We will investigate the hypothesis that abnormalities in the nerve chemicals found in the gut contribute to the aetiology of these diseases. Our studies will examine the sites of action (receptors) for these chemicals (neurotensin and acetylcholine) in the small and large intestine. The mechanisms governing motility changes in response to these chemicals have been well studied in animal intestine, but there is little detailed information from the human intestine. This study will provide insight into the mechanisms operating in the normal bowel, providing a base for comparing bowel obtained from patients with IBD or ICC. We will also study bowel removed at surgery for acute diverticular disease (DD), representing another type of inflammation. Studies on isolated segments of colon from ICC patients will determine whether the contractility of the muscle is abnormal in general or only with respect to the chemicals under investigation. Other studies will investigate the inflammatory processes occurring in the bowel and whether this differs in IBD. Our work will facilitate understanding of the function of the bowel in health and in gastrointestinal disorders and may lead to new medical treatments for IBD and ICC.Read moreRead less
Potential Roles Of 5-hydroxytryptamine In Diseases Affecting The Colon
Funder
National Health and Medical Research Council
Funding Amount
$346,018.00
Summary
The overall aim of this project is to examine the biological roles played by 5-hydroxytryptamine (5-HT) in the human colon. 5-HT is a naturally occurring substance of the body, normally involved in controlling many body activities. Relevance is placed in this project on the possibility that 5-HT is involved in causing or contributing to certain clinical conditions, either by excess or deficiency. The conditions that are the focus of this project are chronic constipation, diverticular disease and ....The overall aim of this project is to examine the biological roles played by 5-hydroxytryptamine (5-HT) in the human colon. 5-HT is a naturally occurring substance of the body, normally involved in controlling many body activities. Relevance is placed in this project on the possibility that 5-HT is involved in causing or contributing to certain clinical conditions, either by excess or deficiency. The conditions that are the focus of this project are chronic constipation, diverticular disease and irritable bowel syndrome. It is a matter of concern that there are no specific treatments for these conditions to date, hence the thrust of the project is to increase knowledge in this area, so hopefully treatments will be developed. Our Pharmacology research group is recognised for its experience in defining drug effects on the intestine and in characterising the target sites on which they act. This has been achieved by using an integrated approach whereby different functional methods reliably detect effects at the levels of the muscle layers, the nerves that supply them and at the absorptive surface using experimental animals. In addition, the use of isolated pieces of human colon obtained from discarded operation material has been an invaluable inclusion into this process. This has allowed us to establish that 5-HT has a target site in the muscle of the colon and that this leads to relaxation and inhibition of the normal spontaneous contractile activity, said anecdotally to be abnormally high in patients with irritable bowel syndrome. We now wish to apply this expertise and knowledge to test whether 5-HT is involved in causing chronic constipation and diverticular disease and to design a drug that would be expected to be of value in treating patients with irritable bowel syndrome.Read moreRead less