Neural Circuits Producing Pelvic Vasodilation In Females
Funder
National Health and Medical Research Council
Funding Amount
$472,770.00
Summary
The reproductive organs and genitalia in males and females experience a large increase in blood flow during sexual and reproductive activity. This increased blood flow (vasodilation) is a key component of penile and clitoral erection, and enhances secretion from the lining of the internal reproductive organs. Vasodilation during sexual activity is produced by a special sets of nerves receiving signals from the genitalia and the brain. In fact, Viagra works by enhancing and prolonging the actions ....The reproductive organs and genitalia in males and females experience a large increase in blood flow during sexual and reproductive activity. This increased blood flow (vasodilation) is a key component of penile and clitoral erection, and enhances secretion from the lining of the internal reproductive organs. Vasodilation during sexual activity is produced by a special sets of nerves receiving signals from the genitalia and the brain. In fact, Viagra works by enhancing and prolonging the actions of these nerves. An important part of this neural pathway is a group of nerve cells in the spinal cord that connects the central nervous system with peripheral nerves in the reproductive organs - these are called preganglionic neurons. Recently we discovered that a major pathway from the spinal cord to the pelvic blood vessels in females leaves the spinal cord at a different level (lumbar) from that thought previously (sacral level). Currently there is no information on how these lumbar preganglionic nerves in females are connected to other nerve pathways that are active during sexual activity, and how they integrate signals from both the internal organs and the brain. We will use an array of modern cellular techniques together with direct observation of dilation in isolated uterine arteries to discover how these nerve cells are wired up in circuits in the spinal cord. This information is vital for us to understand the factors producing increased blood flow in normal sexual activity, and how these might be altered in inflammation or in conditions where there could be selective damage to one nerve pathway and not the other, such as after pelvic surgery, spinal cord damage at different levels, or stimulation of the spinal cord for treatment of chronic pain. Our study also will help understand referred pain and sensations of discomfort in abdominal and pelvic organs.Read moreRead less
Unravelling The Neuropathological Basis Of The Gastrointestinal Manifestations Of Parkinson’s Disease
Funder
National Health and Medical Research Council
Funding Amount
$822,957.00
Summary
Parkinson’s Disease occurs in about 1% of the population. It is a distressing, progressive disease that places a severe burden on patients, families and carers. 80-90% of Parkinson’s Disease patients have constipation which causes substantial distress to patients, their families and carers. We have a rational path to therapy for constipation of Parkinson’s Disease that will be pursued in this project
Sympathetic Control Of Cutaneous Blood Flow And Blood Pressure In Human Spinal Cord Injury
Funder
National Health and Medical Research Council
Funding Amount
$242,002.00
Summary
While spinal cord injury can cause devastating changes in the nervous system paralysis and loss of sensation relatively little is known about changes to the sympathetic nervous system. The sympathetic nervous system is intimately involved in the ongoing control of blood pressure, blood flow and temperature control. Loss of sympathetic control can occur following spinal cord injury. Interruption of descending pathways can result in partial or complete loss of sympathetic outflow from the thoracol ....While spinal cord injury can cause devastating changes in the nervous system paralysis and loss of sensation relatively little is known about changes to the sympathetic nervous system. The sympathetic nervous system is intimately involved in the ongoing control of blood pressure, blood flow and temperature control. Loss of sympathetic control can occur following spinal cord injury. Interruption of descending pathways can result in partial or complete loss of sympathetic outflow from the thoracolumbar segments. Complete decentralization can result in autonomic dysreflexia (autonomic hyperreflexia), in which sensory stimuli originating below the lesion evoke a reflex increase in sympathetic drive to the blood vessels, causing them to constrict. Because of this, blood pressure may rise suddenly and remain at such high levels that stroke and (occassionally) cardiac arrest may occur. This phenomenon, autonomic dysreflexia, is considered a medical emergency. The typical subjective signs of autonomic dysreflexia include a throbbing headache, tingling in the head or nasal congestion; sweating and flushing above the lesion are clinical signs that prompt medical staff to measure blood pressure and to locate the source of sensory irritation (usually a distended bladder or impacted colon, sometimes a pressure sore or ingrown toenail). Commonly, however, subclinical episodes go undetected, and this phenomenon of silent dysreflexia is of increasing concern. This project will develop means of assessing the integrity and state of the sympathetic nervous system below a lesion in patients with spinal cord injury and characterize the firing properties of reflexly activated sympathetic neurones.Read moreRead less
Reduction Of The Cardiovascular Response Of Psychological Stress Through Blockade Of Orexin’s Action On One Of Its Receptors.
Funder
National Health and Medical Research Council
Funding Amount
$394,925.00
Summary
Anxiety, fear of challenges, frustration are part of modern life stressors. Our body reacts to these stressors by increasing blood pressure and heart rate, which in turn can harm our cardiovascular system and precipitate cardiovascular accidents. In this project we test a new class of drugs that act on a neurochemical system implicated in these particular responses. If our hypothesis is correct, one of these drugs could be used to relax the cardiovascular system and protect it in times of stress ....Anxiety, fear of challenges, frustration are part of modern life stressors. Our body reacts to these stressors by increasing blood pressure and heart rate, which in turn can harm our cardiovascular system and precipitate cardiovascular accidents. In this project we test a new class of drugs that act on a neurochemical system implicated in these particular responses. If our hypothesis is correct, one of these drugs could be used to relax the cardiovascular system and protect it in times of stress.Read moreRead less
Investigating The Mechanisms That Increase Nerve-evoked Vasoconstriction Following Spinal Cord Injury
Funder
National Health and Medical Research Council
Funding Amount
$372,547.00
Summary
People with spinal cord injury not only lose control of their arms and legs but also lose control of their bladder and bowel. They also have poor control of blood pressure and an overfull bladder or bowel can lead to dangerously high blood pressure. In this project, we are investigating how this abnormal high blood pressure is generated. The aim is to develop treatments which target the mechanisms which increase the blood pressure responses elicited by the bladder and bowel.