Regulation Of Cellular Responses To Neuropeptides.
Funder
National Health and Medical Research Council
Funding Amount
$83,510.00
Summary
Neuropeptides are chemicals released from nerves that are responsible for communication between the nerves, glands, muscles or other nerves. Neuropeptides exert their diverse biological effects by interacting with small structures on the cells they wish to communicate with. These structures bind the neuropeptide and are termed neuropeptide receptors. The responses of tissues to neuropeptides, for example, contraction of muscle, decrease with continued exposure to the neuropeptide. This reduction ....Neuropeptides are chemicals released from nerves that are responsible for communication between the nerves, glands, muscles or other nerves. Neuropeptides exert their diverse biological effects by interacting with small structures on the cells they wish to communicate with. These structures bind the neuropeptide and are termed neuropeptide receptors. The responses of tissues to neuropeptides, for example, contraction of muscle, decrease with continued exposure to the neuropeptide. This reduction in response is termed desensitization is thought to turn off the response to cells following stimulation by neuropeptides. In this study, I will investigate the mechanisms behind the desensitization of VPAC receptors which are a found throughout the body and have many important roles for example, gastrointestinal, pancreatic and reproductive function and control of muscle. VPAC receptors are also highly expressed in certain many cancers such as breast, prostate and colon carcinoma. The wide variety of functions that these receptors perform and the wide distribution in the body suggest that these are very important receptors. To date research into the responses and desensitisation of these receptors has been lacking, and the work that has been done has become confusing as more receptors and neuropeptides which bind them are discovered. The current project aims to carefully study these receptors and to determine their role in health and disease. The understanding the interaction of receptor and neuropeptide can perhaps lead to development of new therapeutic agents.Read moreRead less
Mechanisms Of Testosterone Action On The Male Pelvic Autonomic Nervous System: The Role Of Estrogens
Funder
National Health and Medical Research Council
Funding Amount
$417,750.00
Summary
The aim of this project is to understand how the circulating hormone, testosterone, affects the autonomic nervous system in adult males. We are particularly interested in the effects this hormone has on the nerve supply of the urogenital organs, ie. the lower urinary tract and reproductive organs. We have already found that many different parts of this pelvic autonomic nervous system are androgen-sensitive, and if the levels of hormones drop significantly, then many properties of the neurons cha ....The aim of this project is to understand how the circulating hormone, testosterone, affects the autonomic nervous system in adult males. We are particularly interested in the effects this hormone has on the nerve supply of the urogenital organs, ie. the lower urinary tract and reproductive organs. We have already found that many different parts of this pelvic autonomic nervous system are androgen-sensitive, and if the levels of hormones drop significantly, then many properties of the neurons change. This is likely to impact negatively on reflexes like penile erection, prostate secretion and propulsion of seminal fluid. Our recent experiments suggest that many of these actions may be caused by testosterone acting in a way that does not involve the typical activation of its receptor molecule (the androgen receptor) and we think it is very likely that it is first converted by some pelvic autonomic neurons into estradiol. We have recently shown that estradiol has potent actions on signalling cascades in these neurons, and that many of the neurons make estrogen receptors. It is also possible that testosterone causes the release of growth factors from the organs, and these growth factors cause changes in their nerve supply. We will investigate both of these possibilities. The outcomes of this study will be relevant for understanding how pelvic autonomic reflexes are affected by endocrine disorders, ageing and various drugs that act on the endocrine system. Our results may also be useful for designing drugs that act on the endocrine system but with less side-effects on the nervous system.Read moreRead less