Voltage Dependent Calcium Channels And Vascular Function: Do Microdomains Determine Function?
Funder
National Health and Medical Research Council
Funding Amount
$597,682.00
Summary
Blood flow depends on arterial diameter which can change with contraction of muscle in the vessel wall. Calcium influx through one type of channel in the muscle cells has been considered critical, but drugs targeting these channels have not succeeded in treating the arterial spasm which occurs after stroke and head injury. Our study will investigate the existence and role of other calcium channels in brain arteries. Knowledge gained will likely lead to development of new drug targets for stroke.
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
A Factorial Randomised Trial Of Intensive Blood Pressure Lowering And Glucose Control In Subjects With Type 2 Diabetes.
Funder
National Health and Medical Research Council
Funding Amount
$303,330.00
Summary
People with diabetes are well known to be at high risk of developing major health problems earlier in life than people without diabetes. In particular, people with diabetes are more likely to suffer from heart attacks, stroke, blindness, kidney failure and leg ulcers that may lead to amputation. Studies of diabetics have shown that if blood pressure levels or glucose levels are uncontrolled, the risk of complications is much higher. Careful management of these two risk factors is therefore now a ....People with diabetes are well known to be at high risk of developing major health problems earlier in life than people without diabetes. In particular, people with diabetes are more likely to suffer from heart attacks, stroke, blindness, kidney failure and leg ulcers that may lead to amputation. Studies of diabetics have shown that if blood pressure levels or glucose levels are uncontrolled, the risk of complications is much higher. Careful management of these two risk factors is therefore now a cornerstone of diabetic care and there are well-established guidelines for treatment. However, there is new evidence to suggest that tighter control of blood pressure and glucose levels than is currently recommended might result in even greater benefits. ADVANCE (Action in Diabetes and Vascular Disease) is a large new study that has been designed by Australian researchers based at the Institute for International Health in Sydney. The aim of ADVANCE is to see if treatment to control blood pressure and glucose levels more tightly than usual reduces the risk of complications among adult diabetics. The study will include 10,000 individuals recruited from about 20 countries worldwide that will be followed for an average of 4.5 years. The first participants will be enrolled in April 2001 and the study results should be available by the end of 2006. There are presently about 300 million people in the world with diabetes and this number is increasing rapidly. The results of ADVANCE will therefore influence the care of a very large number of people. If the findings of the study were positive, implementation of the new treatments could be expected to prevent many tens of thousands of premature heart attacks and strokes around the world each year.Read moreRead less