Does Pregnancy Cause Morphological Changes In Central As Well As Peripheral Nerve Pathways That Control Blood Pressure?
Funder
National Health and Medical Research Council
Funding Amount
$382,538.00
Summary
Pregnancy changes blood pressure but the mechanism is unknown. We will use state-of-the-art anatomical methods to define how pregnancy alters nerves controlling blood pressure. We will identify changes in the information the nerve cells receive, in their shape and in the way they communicate with other blood pressure-controlling nerve cells. This information will help to develop new ways to prevent and treat pre-eclampsia, a major cause of death and disability for mothers and their newborns.
Mechanisms Underlying Increased Cardiac And Renal Noradrenaline Spillover During Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$492,681.00
Summary
Heart failure is associated with increased release of the neurotransmitter noradrenaline from sympathetic nerves to the heart and the kidney. The raised levels of this neurotransmitter in the heart and the kidney are harmful and lead to reduced survival in heart failure patients. This project will increase our understanding of the mechanisms that control noradrenaline release and may lead to better treatment paradigms to target the detrimental increase in release in heart failure.
Role Of The Hypothalamus, Oxidative Stress And Angiotensin In Chronic Stress
Funder
National Health and Medical Research Council
Funding Amount
$535,333.00
Summary
Stress can trigger life threatening cardiovascular events and its impact is much greater when blood pressure is raised. We seek to determine which chemical type of brain neuron and which region is responsible for amplifying the responses to repeated stress in an animal model that closely resembles the human form of the disease. We will focus specifically on the hypothalamus which controls the sympathetic nervous system.
Effects Of Ghrelin Receptor Ligands On Cardiovascular Function
Funder
National Health and Medical Research Council
Funding Amount
$516,207.00
Summary
Ghrelin is a hormone that is known to control food intake and growth hormone release. Our recent work shows that compounds that mimic ghrelin�s actions influence blood pressure by their effects in the brain, the spinal cord and on arteries. We will investigate the potential of such compounds to treat blood pressure disorders
An Examination Of The Contribution Of Visceral Adiposity To Insulin Resistance In Humans.
Funder
National Health and Medical Research Council
Funding Amount
$335,800.00
Summary
The worldwide epidemic of Type 2 diabetes is related to major nutritional and activity changes interacting with a genetic predisposition. The two key defects in Type 2 diabetes are a reduced response to insulin (insulin resistance) and relative failure of insulin production. Insulin resistance is the earliest defect and is closely associated with cardiovascular risk. Obesity generates insulin resistance, but intraabdominal (visceral) fat has particular importance. Visceral fat cells are differen ....The worldwide epidemic of Type 2 diabetes is related to major nutritional and activity changes interacting with a genetic predisposition. The two key defects in Type 2 diabetes are a reduced response to insulin (insulin resistance) and relative failure of insulin production. Insulin resistance is the earliest defect and is closely associated with cardiovascular risk. Obesity generates insulin resistance, but intraabdominal (visceral) fat has particular importance. Visceral fat cells are different to other fat cells; they are very metabolically active and 'spill out' fatty acids indiscriminately contributing to insulin resistance in liver and muscle; they also produce hormones which may modify the action of insulin. We will study people undergoing abdominal surgery. Participants will be (1) normal weight and sensitive to insulin, (2) abdominally overweight and insulin resistant, (3) insulin resistant with Type 2 diabetes. We will document abdominal fat, circulating lipid and hormone levels and insulin action. At surgery fat biopsies will be obtained from (a) inside the abdominal cavity, (b) the fat layer under the abdominal skin and (c) fat in the buttock. The activity of a large number of genes in the fat tissue will be assessed in 8 subjects using DNA array (4 each from Groups 1 and 2). Then a small number of genes will be selected on the basis of different activity in visceral fat from buttock fat, and between insulin sensitive and insulin resistant people. The activity of these genes will be determined in all subjects in the 3 groups. We anticipate identifying a few (perhaps 3) genes whose activity is closely associated with insulin resistance and will examine their capability to block insulin action in a series of animal and cellular studies. These studies should identify specific mechanisms by which visceral fat creates insulin resistance. This would be an important step towards prevention and improved medication for Type 2 diabetes.Read moreRead less
Central Control Of Blood Pressure: Neurotransmitters, Receptors, Signal Transduction And Gene Expression
Funder
National Health and Medical Research Council
Funding Amount
$941,350.00
Summary
The way that the brain controls blood pressure is of crucial significance to our day-to-day survival. Nerves in the lower brain and spinal cord cause blood pressure to be maintained at appropriate levels for all types of daily activities ranging from sleep, when blood pressure is very low, to exercise when blood pressure can be very high. In hypertension, a disorder that afflicts around 10% of the community, blood pressure is elevated to an extent that damages organs such as the brain, heart, ki ....The way that the brain controls blood pressure is of crucial significance to our day-to-day survival. Nerves in the lower brain and spinal cord cause blood pressure to be maintained at appropriate levels for all types of daily activities ranging from sleep, when blood pressure is very low, to exercise when blood pressure can be very high. In hypertension, a disorder that afflicts around 10% of the community, blood pressure is elevated to an extent that damages organs such as the brain, heart, kidney and eye. It now appears that most cases of hypertension have as their basis a disorder of the way that the brain, through the sympathetic nervous system, controls the heart and blood vessels. Many different brain systems need to change the way that blood is distributed in the body at different times. For example, when we eat, blood goes preferentially to our gut; if we exercise, to our heart and muscles; if we are cold, to our skin and when we think, to our brain. This specialised regulation of blood flow is accomplished by the interaction of nerves in the lower brain and spinal cord. It involves a vast array of special chemical messengers acting on specific receptors through different intracellular mechanisms and involving the turning on or off of genes. Only a few of these neurotransmitter systems are well understood. At the core of our proposal, we aim to determine which neurotransmitters systems are important for which cardiovascular functions. We anticipate that this new information will permit the development of new approaches to the management of hypertension. The reason for this is that since different pathways use different messenger systems, it should become possible to tailor therapy to suit hypertension without causing undesirable side-effects.Read moreRead less