Differentiation Of Multiple Phenotypes Of Rostral Ventromedial Medulla Neurons And Their Role In Pain
Funder
National Health and Medical Research Council
Funding Amount
$285,990.00
Summary
Chronic pain, defined as pain experienced in three out of a six month pre-interview period affects 17% of males and 20% of females in the Australian population. Opioid drugs such as morphine and codeine are the most effective drugs used to treat moderate to severe pain. However, the utility of these drugs is hampered by the development of a blunted response with repeated use. Furthermore, some clinically important pain states, particularly those caused by nerve injury, do not respond well to opi ....Chronic pain, defined as pain experienced in three out of a six month pre-interview period affects 17% of males and 20% of females in the Australian population. Opioid drugs such as morphine and codeine are the most effective drugs used to treat moderate to severe pain. However, the utility of these drugs is hampered by the development of a blunted response with repeated use. Furthermore, some clinically important pain states, particularly those caused by nerve injury, do not respond well to opioid drugs. Recent basic neurosceince research has identified groups of nerve cells deep within the brain that control sensitivity to pain as pain signals enter the spinal cord. Unfortunately in the presence of some chronic pain conditions, or chronic use of high doses of opioid drugs, these neurons undergo functional changes or adaptations that distort and increase the severity of pain sensation in a more or less permanent manner. This project uses electrical and chemical techniques to identify the basic physiology and pharmacology of single nerve cells in this brain region, so that their normal functions can be properly understood. We will then identify the cellular and molecular adaptations that occur in the nerve cells in animal models of chronic nerve injury and chronic morphine treatment to identify the nature of adaptations responsible for their aberrant function. We will then be in a position to rationally identify novel drug targets that can normalise the function of these nerve cells. This knowledge will provide potential targets for development of novel therapeutics to manage chronic pain.Read moreRead less
Post Synaptic Density Scaffold Proteins In The Growth Cone: Homer And Shank, Crucial For Calcium Signaling.
Funder
National Health and Medical Research Council
Funding Amount
$237,909.00
Summary
Our brain is a complex, yet precise electrical circuit. Understanding how the embryonic brain is wired has direct implications for all aspects of life, from the growing foetus in mother's womb, to learning algebra and for maintaining the active memories of our ageing population. This project aims to provide new insight into understanding how the embryonic brain is wired, crucial information for future pharmacological or gene therapy approaches to mental illness, ageing, and neuronal injury.
Modulation Of Calcium Signalling By Acetylcholine In The Basolateral Amygdala
Funder
National Health and Medical Research Council
Funding Amount
$266,748.00
Summary
The amygdala is an area of the brain involved in assigning emotional significance to sensory stimuli. This grant examines the cellular processes involved in making these associations. Specifically, it studies the relationship between two signalling molecules implicated in association learning, acetylcholine and calcium. This research will test hypotheses of memory formation and provide insight into disorders linked to detrimental emotional associations, such as anxiety and addiction.
Novel Substance P Receptors On Autonomic And Sensory Neurons Regulating The Viscera
Funder
National Health and Medical Research Council
Funding Amount
$447,750.00
Summary
Potentially harmful stimulation of the skin or the internal organs activates sensory nerves that send signals to the brain. These events often are perceived as painful. One chemical messenger transmitting these signals first to the spinal cord, and then to the brain, is a neuropeptide called substance P. During many chronic inflammatory conditions, such as inflammation of the bowel, these signalling pathways are sensitised so that stimuli that previously were not painful now are perceived as pai ....Potentially harmful stimulation of the skin or the internal organs activates sensory nerves that send signals to the brain. These events often are perceived as painful. One chemical messenger transmitting these signals first to the spinal cord, and then to the brain, is a neuropeptide called substance P. During many chronic inflammatory conditions, such as inflammation of the bowel, these signalling pathways are sensitised so that stimuli that previously were not painful now are perceived as painful. This sensitisation has several different causes. One contributing factor seems to be related to a change in the receptor molecules that recognise substance P. Last year we discovered a new type of receptor for substance P, that is prominent in the nerve pathways between the gut and the spinal cord. This novel receptor has important characteristics that are different from the classical substance P receptor. However, we are still largely ignorant about how substance P interacts with these new receptors to modify the activity of nerve cells in sensory pathways. Indeed, we propose that these new receptors are likely to make a significant contribution to the sensitisation that occurs in inflammation. We will use a combination of sophisticated cellular and molecular techniques to study the way in which substance P acts on these novel receptors in nerves regulating the visceral organs. Our results are likely to make a significant contribution to the development and interpretation of rational new therapies for treating chronic diseases of the gastrointestinal tract, such as inflammatory bowel disease (IBD). Our studies will reveal signalling mechanisms that also are likely to be used by substance P more widely in the nervous system, that are relevant to other inflammatory conditions like arthritis, and even some forms of depression.Read moreRead less
Roles Of Brain-derived Neurotrophic Factor In Plasticity Of Injured Sensory Neurons
Funder
National Health and Medical Research Council
Funding Amount
$461,443.00
Summary
The fundamental problem of how nerve cells respond to a nerve injury has long been studied by neuroscientists and clinicians. After a nerve injury outside the brain or spinal cord, ie, in the periphery, some sensory nerve cells die, some regenerate to reconnect to their targets, and some sprout to make abnormal connections. Recent evidence from our lab and others indicates that the nerve sprouting is linked to chronic pain experienced by nerve-injury patients. However, how these changes occur st ....The fundamental problem of how nerve cells respond to a nerve injury has long been studied by neuroscientists and clinicians. After a nerve injury outside the brain or spinal cord, ie, in the periphery, some sensory nerve cells die, some regenerate to reconnect to their targets, and some sprout to make abnormal connections. Recent evidence from our lab and others indicates that the nerve sprouting is linked to chronic pain experienced by nerve-injury patients. However, how these changes occur still remains largely unknown. Our recent studies showed that growth factors, particularly brain-derived neurotrophic factor (BDNF) which is made by the sensory nerve cells, may play important roles in mediating these changes. This proposed project, directly evolved from our recent exciting findings, aims to further examine roles and action mechanisms of BDNF and its relatives in regulating the responses of sensory nerve cells to a nerve injury. We propose that after an injury, BDNF promotes survival of some nerve cells, enhances sensory nerve regeneration in both periphery and spinal cord, and also mediates abnormal nerve sprouting and is involved in neuropathic pain. With strong expertise and powerful tools in hand, we have designed a series of experiments to investigate the roles and action mechanisms of BDNF and its related molecules in these processes. Results from this project will help us understand mechanisms underlying the responses of nerve cells to a nerve injury, and should provide much needed information which would help in designing new methods for enhancing nerve cell survival and nerve regeneration as well as for inhibiting nerve injury-induced chronic pain in nerve-injury patients.Read moreRead less