Heart failure is a severely debilitating condition with a poor prognosis. It is characterized by retention of fluid and high nervous activity especially to the kidneys and the heart. Even with the best current treatment available, patients with heart failure still suffer from abnormally high nerve activity to the further detriment of this condition. The successful completion of this project will provide considerable insight into the role of the brain in the elevated nerve activity in heart failu ....Heart failure is a severely debilitating condition with a poor prognosis. It is characterized by retention of fluid and high nervous activity especially to the kidneys and the heart. Even with the best current treatment available, patients with heart failure still suffer from abnormally high nerve activity to the further detriment of this condition. The successful completion of this project will provide considerable insight into the role of the brain in the elevated nerve activity in heart failure. It will also provide us with a significant understanding of the role in reflex sympathetic nerve regulation of an important brain region known as the hypothalamic paraventricular nucleus (PVN). Our findings will help us understand the nature of the neurotransmitters contributing to the reflex nerve regulation and the specific neurons within the PVN involved. This knowledge could help us to identify novel potential therapeutic targets within the brain to alleviate the problems observed in heart failure.Read moreRead less
Role Of The Medial Amygdala In Developing Neurogenic Hypertension
Funder
National Health and Medical Research Council
Funding Amount
$302,123.00
Summary
We aim to investigate the underlying mechanisms and pathways that regulate the activity of neurons located in the medial amgydala during stress that contribute long term to the development of hypertension. This study is highly relevant to people who inappropriately respond to typical daily stressors and we aim to provide direction for developing specific therapies to interrupt the adverse cardiovascular consequences of chronic stress.
The brain regulates body temperature by a series of mechanisms, including the control of how much blood flows to the skin to lose or retain heat. The project aims to locate the brain temperature receptors and brain pathways that do this, using an animal model, the rat. At present they are not known.
Understanding The Origins Of Neurogenic Hypertension
Funder
National Health and Medical Research Council
Funding Amount
$668,914.00
Summary
Brain cells that control the cardiovascular system are thought to have stopped dividing by adulthood. We recently discovered that this is not the case. Our initial findings suggest that these nascent cells might be important for maintaining normal blood pressure. This work will allow us to elucidate the function of these nascent cells and how they integrate into the circuit that controls the cardiovascular system. Our findings will be fundamental for understanding diseases such as hypertension.
Mechanisms Behind The Activation Of Cardiac And Renal Sympathetic Nerve Activity In Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$452,670.00
Summary
Heart failure is associated with an increase in messages from the brain that control how fast the heart beats but the factors involved remain poorly understood. This project will enable a better understanding ot the mechanisms controlling this increase in the activity of the nerves. This understanding will provide a new avenue for therapy and for the development of new treatments.
Inadequately controlled blood pressure remains the leading cause of death world wide despite the availability of numerous effective drugs. We have successfully pioneered a catheter-based approach using radiofrequency-energy to disrupt renal nerves and lower blood pressure in patients with resistance to conventional drug treatment. We now aim to test the role of this ground-breaking technology as a potential cure (blood pressure control without antihypertensive medication) for hypertension.
Contribution Of The Central Nervous System To Peripheral Neural Control In Obesity And Diabetes.
Funder
National Health and Medical Research Council
Funding Amount
$454,691.00
Summary
Obesity and diabetes are becoming major worldwide public health problems. A characteristic of human obese diabetes is a marked increase in sympathetic nerve activity to the kidneys and to the muscle. The cause of this overactivity is unknown, but undoubtedly involves the central nervous system. Within the brain are a select group of regions that are able to directly influence the activation of the sympathetic nervous system. We suspect these areas to play a critical role in the overactivity of t ....Obesity and diabetes are becoming major worldwide public health problems. A characteristic of human obese diabetes is a marked increase in sympathetic nerve activity to the kidneys and to the muscle. The cause of this overactivity is unknown, but undoubtedly involves the central nervous system. Within the brain are a select group of regions that are able to directly influence the activation of the sympathetic nervous system. We suspect these areas to play a critical role in the overactivity of the sympathetic nerve activity in obese diabetics. Indeed, we believe that there are specific chemical messengers in these select brain areas that are normally finely balanced. In obesity - diabetes, this balance is disturbed. Finally, we hypothesise that exercise, which is known to have beneficial effects for obesity - diabetes, restores the balance of the neurochemicals and this contributes to the positive outcomes of exercise.Read moreRead less
Control Of Sympathetic Nerves That Talk To The Immune System
Funder
National Health and Medical Research Council
Funding Amount
$385,958.00
Summary
The two complex systems of the body, the immune system and the nervous system, communicate with each other. This proposal studies one of the major pathways from brain to immune system - sympathetic immuno-efferent nerves. In stroke, these pathways cause profound immunosuppression, causing susceptibility to infection. Their poorly understood central and peripheral pathways will be defined and mapped by this study.
Sympathetic Nervous System Contribution To Hypertension : CNS Pathways, Neurotransmitters And Neuroeffector Mechanisms
Funder
National Health and Medical Research Council
Funding Amount
$450,750.00
Summary
High blood pressure (hypertension) is a major public health problem in Western society with approximately 20% of adults affected. If left untreated, serious damage to organs can occur and the risk of sudden cardiac death or stroke is greatly increased. While many factors contribute to the development of hypertension such as lifestyle, genes, diet, weight and exercise levels, a common feature in the early stages is an overactive nervous system in the kidney and in the heart which is most likely d ....High blood pressure (hypertension) is a major public health problem in Western society with approximately 20% of adults affected. If left untreated, serious damage to organs can occur and the risk of sudden cardiac death or stroke is greatly increased. While many factors contribute to the development of hypertension such as lifestyle, genes, diet, weight and exercise levels, a common feature in the early stages is an overactive nervous system in the kidney and in the heart which is most likely due to altered signals from the brain. We need to understand why this occurs. One possibility is that renin (a chemical released from the kidney) that is known to control body fluid, also acts in the brain to increase nerve activity to the kidney and heart and in this way contributes to high blood pressure. It does this indirectly by producing another hormone called angiotensin. Our research has shown that in conditions where the kidney releases excess of the hormone renin, which may occur if the blood supply to the kidney is reduced, a change occurs in the way in which the nervous system affects blood pressure. The nervous system is activated to increase the release of renin from the kidney. The effect of this is to make blood pressure increase further in what can become a vicious circle. At present it is not understood why and how this change occurrs. The major thrust of this project is to determine the mechanims by which the renal hormones signal the central nervous system to change the nature of the nervous activity back to the kidney. We want to know what parts of the brain are involved, how the nature of the activity in the nerves changes and also how the nervous control of the kidney changes (i.e. how the kidney changes its responsivness to the nerve activity). Because similar processes probably occur in nearly all forms of high blood pressure, our results will greatly improve our understanding of how this dangerous condition develops.Read moreRead less
BRAIN IMAGING OF CARDIOVASCULAR CONTROL DURING MUSCLE PAIN
Funder
National Health and Medical Research Council
Funding Amount
$370,983.00
Summary
One in every five people in Australia suffers chronic pain and a third of these have severe pain associated with severe disability. The incapacitating effects of long-lasting pain are not just psychological, but affect many systems, including the cardiovascular system. We are interested in why pain causes blood pressure to increase in some people but not in others: patients with post-surgical chronic pain have nearly twice the prevalence of clinical hypertension than patients without pain.