Neurotransmitters In Synaptic Inputs To Medullary Neurons Subserving The Baroreflex
Funder
National Health and Medical Research Council
Funding Amount
$470,500.00
Summary
The baroreflex rapidly adjusts arterial blood pressure to meet changing physiological needs. The reflex alters vascular resistance and changes the rate, volume and force at which blood is expelled from the heart, ensuring that organs are adequately supplied with blood-borne nutrients and oxygen. Changes in baroreflex function occur during exercise, correlate with increased mortality and morbidity from heart failure and myocardial infarction and are responsible for postural hypotension in the eld ....The baroreflex rapidly adjusts arterial blood pressure to meet changing physiological needs. The reflex alters vascular resistance and changes the rate, volume and force at which blood is expelled from the heart, ensuring that organs are adequately supplied with blood-borne nutrients and oxygen. Changes in baroreflex function occur during exercise, correlate with increased mortality and morbidity from heart failure and myocardial infarction and are responsible for postural hypotension in the elderly. Three areas in the brainstem are critical for transmission of the arterial baroreflex. However, it is still not known exactly which chemicals (neurotransmitters) are used to convey baroreflex information to and between neurons in these key sites. In this project, we will use state-of-the-art anatomical techniques to examine nerve pathways that subserve the arterial baroreflex. By changing blood pressure and specifically tagging nerve cells that respond, we can focus on neurons activated by baroreflex stimuli. Concentrating on neurotransmitters known to affect blood pressure control in the medulla, we will then label one or more of these in nerve fibers surrounding the barosensitive neurons. Finally, we will determine by light and electron microscopy the relationships between the labelled nerve fibers and the barosensitive neurons. These relationships will show which neurotransmitters could influence barosensitive neurons directly, which indirectly and which not at all. This project will increase our understanding of the baroreflex by clarifying which neurochemicals convey baroreflex information amongst the key groups of brainstem neurons. These data will form the foundation for new studies on changes in nerve pathways that underlie baroreflex dysfunction in such conditions as postural hypotension. Identifying transmitters for the baroreflex may also point to, or rule out, new drug treatments for disturbances in baroreflex function.Read moreRead less
Is Insulin Sensitivity In Children And Their Mothers Programmed By Maternal Blood Glucose?
Funder
National Health and Medical Research Council
Funding Amount
$169,630.00
Summary
Glucose intolerance in pregnancy is associated with the birth of large-for-dates and macrosomic (>4000g) babies. The risk of type 2 diabetes is greater in babies who are small or large at birth compared to those with normal birth weight. This study will determine if treatment of mothers with glucose intolerance in pregnancy (which is intermediate between normal glucose tolerance and diabetes) alters the regulation of glucose tolerance in their children. The mothers were randomised to receive ....Glucose intolerance in pregnancy is associated with the birth of large-for-dates and macrosomic (>4000g) babies. The risk of type 2 diabetes is greater in babies who are small or large at birth compared to those with normal birth weight. This study will determine if treatment of mothers with glucose intolerance in pregnancy (which is intermediate between normal glucose tolerance and diabetes) alters the regulation of glucose tolerance in their children. The mothers were randomised to receive normal antenatal care or to have their blood sugar measured and controlled by diet and insulin as for diabetics. We will measure the insulin sensitivity of the children to a glucose load. We will also measure blood pressure and lipids in these children. Treatment of the mother during pregnancy may alter the deposition of fat in the fetus the effect of which will continue into childhood. Thus the offspring of treated mothers may remain thinner throughout childhood. Each pregnancy increases a woman's chance of developing type 2 diabetes in later life. This risk is further increased by abnormal glucose tolerance during pregnancy. This study will test the long-term benefits of treatment during pregnancy of women with impaired glucose tolerance on the subsequent regulation of glucose tolerance. We shall invite women who took part in the Australian Carbohydrate Study in Pregnancy (ACHOIS) to return and have an intravenous glucose tolerance test. Insulin sensitivity and glucose tolerance will be determined and related to treatment of the impaired glucose tolerance in pregnancy. This study will be the first follow-up of a large randomised trial of treatments of impaired glucose tolerance in pregnancy. The potential long-term benefits are strategies to reduce the future chance of developing risk factors for type 2 diabetes, obesity and abnormal blood lipids in childhood and adult life. The study will establish the benefits or otherwise of tight control of blood glucose in pregnancy.Read moreRead less
Chromatin Dynamics During Sexual Differentiation In The Malaria Parasite P. Falciparum
Funder
National Health and Medical Research Council
Funding Amount
$535,858.00
Summary
Inhibiting malaria transmission is a critical step towards global eradication of this deadly disease. This proposal aims to understand the mechanisms regulating the expression of genes which control the differentiation of the transmission stages of malaria parasites. Such pathways are prime targets for novel anti-malarial drugs.