A group of nerves, called sensory nerves, supply most body organs including the uterus, and are well known to transmit information to the brain. It is now known that these nerves are also capable of releasing the chemicals (neuropeptides) from their endings within these body organs to affect their function. In the uterus these chemicals cause the uterus to contract. We have shown that neuropeptides known as tachykinins are effective in lower concentrations when applied to small specimens of uter ....A group of nerves, called sensory nerves, supply most body organs including the uterus, and are well known to transmit information to the brain. It is now known that these nerves are also capable of releasing the chemicals (neuropeptides) from their endings within these body organs to affect their function. In the uterus these chemicals cause the uterus to contract. We have shown that neuropeptides known as tachykinins are effective in lower concentrations when applied to small specimens of uterine tissue taken from non-pregnant women at hysterectomy than when applied to similar uterine specimens taken from pregnant women at caesarean section. The aim of this project is twofold. Firstly, we want to know why the tachykinins are more potent in uterine tissue from non-pregnant women. Possible explanations that we will examine are that tissues from non-pregnant women contain more sites of action at which the peptides can act, or alternatively, that there is decreased breakdown of these tachykinins in uterine tissue from non-pregnant women. This could occur if a substance known to break down the tachykinins in the uterus shows greater activity during pregancy than when a woman is not pregnant. Secondly, we wish to find out if other chemicals (substances that can produce inflammatory responses, and in particular a group of chemicals known as prostaglandins), that are known to be present in greater amounts in the tissues of women during disease states such as dysmenorrhoea, can cause the release of the neuropeptides that we are studying. If they do cause such a release of tachykinins, this could be an important factor contributing to the disease state. Our hypothesis is that tachykinins and the substances which can break them down may play an important role in regulating uterine contractility in non-pregnant and to a lesser degree in pregnant women.Read moreRead less
Properties And Electro-Physiology Of The Intrinsic Nervous System
Funder
National Health and Medical Research Council
Funding Amount
$419,214.00
Summary
The gut contains a very large number of nerve cells which fall into several functionally distinct groups. We have identified virtually all these functional groups in the guinea-pig small intestine and have begun an analysis of the ways the different groups communicate with each other. We have developed methods to identify the functions of any nerve cell from which we record and have also developed novel methods for specifically stimulating individual functional classes of nerve cells that contac ....The gut contains a very large number of nerve cells which fall into several functionally distinct groups. We have identified virtually all these functional groups in the guinea-pig small intestine and have begun an analysis of the ways the different groups communicate with each other. We have developed methods to identify the functions of any nerve cell from which we record and have also developed novel methods for specifically stimulating individual functional classes of nerve cells that contact them. The aim of the proposed research is to exploit these methods to identify the chemicals used by specifc types of nerve cell in transmission of information to other nerve cells during the normal behaviour of the intestine. We will record the behaviour of individual nerve cells in the gut wall while stimulating specific nerve pathways that contact them. We will then use drugs that block the activity of the chemicals of interest (small proteins called tachykinins, and certain amine compounds) to try and block the transmission of information between the nerve cells involved. Identification of the nature of the chemicals used at specific connections between different functional groups of nerve cells in the gut will allow the design of drugs for treatment of gastrointestinal disorders that will have minimal side effects. Further because the chemicals that are used for communication in the gut are also found in the brain, the results will provide evidence about the functions of these chemicals elsewhere in the nervous system.Read moreRead less