Pontine control of adaptive breathing behaviour in health and disease. This project will develop an understanding of the fundamental brain mechanisms associated with adaptive breathing during behaviour such as speech or swallowing. Adaptive breathing is impaired in lung disease, dementia and autism. This project will provide new insight to global brain function and treatment of central respiratory disorder.
A novel sensory neural circuit has been identified innervating the airways and lungs. The anatomical organisation of this circuit has been described to some extent in previous studies, however there is a significant gap in knowledge with respect to its functional importance. This project will develop methods to address this knowledge gap and in doing so the project will firstly describe how this circuit controls breathing under normal conditions and secondly how this becomes dysregulated during
Neural Basis Of The Thermal Instability That Leads To Menopausal Hot Flushes
Funder
National Health and Medical Research Council
Funding Amount
$330,535.00
Summary
Hot flushes and night sweats affect 80-90% of women during the menopause transition. In 20% of women these symptoms are severe. The mechanisms are not well understood, and non-hormonal treatments are urgently needed. We can investigate the basic brain mechanisms in an animal model, the sheep. The findings will elucidate the mechanisms that disrupt normal temperature regulation and thus lead the way to better therapies for this common, and often debilitating, condition. .
Mapping sites of visceral convergence connecting the colon and bladder. This project aims to develop multiple neuroanatomical approaches to identify where in the central nervous system the sensory signalling from the colon and bladder merge. The combination of such technologies is novel to the study of the central circuits relaying colon/bladder convergence into the brain and will generate new and detailed knowledge of the central pathways in which pelvic organ sensory (discomfort) and motor (de ....Mapping sites of visceral convergence connecting the colon and bladder. This project aims to develop multiple neuroanatomical approaches to identify where in the central nervous system the sensory signalling from the colon and bladder merge. The combination of such technologies is novel to the study of the central circuits relaying colon/bladder convergence into the brain and will generate new and detailed knowledge of the central pathways in which pelvic organ sensory (discomfort) and motor (defecation/urination) functions are coordinated. The expected outcomes are predicted to aid future discovery of mechanisms of cross-organ sensitisation and are anticipated to provide significant benefit to therapy development for chronic visceral pain syndromes associated with bowel and bladder dysfunction.Read moreRead less
The jugular vagal sensory connectome regulating visceral function. Internal body organs have a rich supply of sensory nerve fibres that serve important roles in monitoring the local environment for normal and abnormal sensory stimuli. These nerve fibres have different origins and wire into brain circuits that regulate widely diverse physiological responses. In this study we aim to study the neural circuits and responses mediated by a group of these sensory nerves which has not been investigated ....The jugular vagal sensory connectome regulating visceral function. Internal body organs have a rich supply of sensory nerve fibres that serve important roles in monitoring the local environment for normal and abnormal sensory stimuli. These nerve fibres have different origins and wire into brain circuits that regulate widely diverse physiological responses. In this study we aim to study the neural circuits and responses mediated by a group of these sensory nerves which has not been investigated appreciably in the past. We believe that these sensory neural circuits will reveal important new insights into how internal organs perform their diverse and essential functions to sustain life.Read moreRead less
I am a medically trained physiologist studying how the brain controls the delivery of oxygen to the body, the removal of carbon dioxide and the maintenance of normal acid level in the blood. This branch of physiology is well known to anyone who has studied 'ABC' in a first aid programme. My work concerns the coordination of the breathing and blood pressure centres in the brain. It is crucial in the understanding of diseases such as obstructive sleep apnoea and hypertension.
How Does The Central Respiratory Generator Amplify Sympathetic Activity In Hypertension?
Funder
National Health and Medical Research Council
Funding Amount
$290,113.00
Summary
High blood pressure causes many life-threatening cardiovascular diseases, including heart failure and stroke. The cause of most high blood pressure is not known. Using an animal model of high blood pressure we have shown that an interaction, in the brain, between the nerve pathways that generate respiratory activity and regulate blood pressure is altered. This occurs early in life and our evidence strongly suggests this may be a cause of high blood pressure.
ORIGIN AND REGULATION OF VAGAL PREGANGLIONIC NEURON SUBTYPES CONTROLLING AIRWAY SMOOTH MUSCLE TONE
Funder
National Health and Medical Research Council
Funding Amount
$438,700.00
Summary
The primary role of the airways is to allow the exchange of oxygen and carbon dioxide between the environment and the lungs. However, the airways are not merely a series of static tubes, but rather their size (or caliber) is subject to breath-by-breath alterations, thereby regulating gas exchange to match the body's demands. Regulation of airway caliber is achieved largely by subconscious changes in the tone of the muscle lining the airway wall. Airway muscle tone is primarily under the control ....The primary role of the airways is to allow the exchange of oxygen and carbon dioxide between the environment and the lungs. However, the airways are not merely a series of static tubes, but rather their size (or caliber) is subject to breath-by-breath alterations, thereby regulating gas exchange to match the body's demands. Regulation of airway caliber is achieved largely by subconscious changes in the tone of the muscle lining the airway wall. Airway muscle tone is primarily under the control of the parasympathetic division of the autonomic nervous system. Two distinct types of parasympathetic nerves innervate the airways: One type employs the neurotransmitter acetylcholine which causes airway muscle to contract and the airways to constrict, while the other type employs nitric oxide which evokes airway dilatation. The normal regulation of airway caliber is altered in a variety of inflammatory airways diseases. In asthma and chronic obstructive pulmonary disease (COPD) there is an increase in airway muscle tone (airway constriction) which compromises the normal movement of gasses and contributes to the morbidity and mortality of the diseases. There is a growing body of evidence to suggest that exaggerated airway muscle tone may in part result from dysfunction of either the contractile or relaxant parasympathetic nerves innervating the airways. However, at present very little is known about the parasympathetic pathways regulating airway caliber. A complete understanding of the mechanisms controlling airway smooth muscle tone is therefore essential to fully understanding possible role of autonomic dysfunction in the pathogenesis of obstructive airways diseases. The aim of this grant is to better define the physiological and anatomical properties of airway parasympathetic nerves in the brain stem.Read moreRead less
Respiratory Modulation Of RVLM Premotor Neurons: Role In The Sympathetic Over-activity Of Hypertension.
Funder
National Health and Medical Research Council
Funding Amount
$338,605.00
Summary
Hypertension is a common health disorder in all societies and is a major risk factor for the development of life threatening cardiovascular diseases, including heart failure and stroke. Whilst some effective therapies are available, many patients are not adequately treated or have reduced quality of life due to serious side effects. There is a great need for alternative therapies. The central nervous system is clearly involved in hypertension although the level of that involvement is not well un ....Hypertension is a common health disorder in all societies and is a major risk factor for the development of life threatening cardiovascular diseases, including heart failure and stroke. Whilst some effective therapies are available, many patients are not adequately treated or have reduced quality of life due to serious side effects. There is a great need for alternative therapies. The central nervous system is clearly involved in hypertension although the level of that involvement is not well understood- i.e. is it a causal factor or just a contributor to the maintenance of established hypertension? The experiments outlined in this application are based on the observation that modulation of nervous activity to blood vessels is more influenced by the respiratory system in people with high blood pressure, than in normotensive people. We aim to test whether this increased respiratory modulation might be involved in the generation of the high blood pressure.Read moreRead less
Rhombomeric Topography of Structures in the Adult Mouse: Evidence from Avian Homologies and Transgenic Mice. The brainstem of birds has been shown to be formed by a line of segments, like carriages of a train. The same arrangement exists in the embryos of mammals, but is hidden in the adult mammalian brain. We will transfer our detailed knowledge of bird brains to make a maps of the brainstem segments in adult mice. We will then test this map with special gene markers which will reveal the occul ....Rhombomeric Topography of Structures in the Adult Mouse: Evidence from Avian Homologies and Transgenic Mice. The brainstem of birds has been shown to be formed by a line of segments, like carriages of a train. The same arrangement exists in the embryos of mammals, but is hidden in the adult mammalian brain. We will transfer our detailed knowledge of bird brains to make a maps of the brainstem segments in adult mice. We will then test this map with special gene markers which will reveal the occult segmental pattern in adult mice. This work will give us a new way of understanding the organisation of brainstem centres that control breathing, cardiovascular functions and emotional states.Read moreRead less