Quick Project Snapshot

Inhibitory mechanisms within the nucleus of the solitary tract

The nucleus of the solitary tract (NTS) is the first central site to receive viscerosensory afferent input and is involved in mediating autonomic reflexes (e.g. baroreflex). Autonomic reflexes are highly flexible and dynamic. For example during exercise, where both blood pressure and heart rate both remain high over sustained periods, the baroreflex seemingly decoupled during this period.

This project aims to determine the synaptic mechanisms underlying reflex strength and flexibility. Specifically, how inhibitory synaptic gating mechanisms affect synaptic transmission between viscerosensory afferents and NTS neurons utilizing a channelrhodopsin 2 expressing mouse line.


Figure. Using optogenetics to study the inhibitory network within NTS. A. Experimental concept. B. Horizontal medulla slice from a SST-ChR2-YFP mouse. C. LED pulse evokes Inhibitory post synaptic currents in NTS neurons.

Dr Stuart McDougall

Viscerosensory Laboratory

We study the basic neurophysiology underpinning integration of sensory information within the brain. Our focus of study is at the level of the nucleus of the solitary tract (NTS), a region in the brain that first receives signals from visceral organs including those of the cardiovascular, respiratory and gastro intestinal systems. Knowledge about how the brain and internal organs co-ordinate is pertinent to several disease states, autonomic related; hypertension and obesity and mental health; stress and depression.

Sensory signals concerning internal organ function is termed ‘vicserosensory’, blood pressure for example. We study how the neural network within the NTS is organised; how vicserosensory information modifies behaviour (salt appetite) and visceral organ function during disease (hypertension). Equally, how behaviour (stress/depression) and disease (obesity) modify autonomic reflexes to alter visceral organ function.

The primary techniques utilised within the laboratory revolve around in vitro slice electrophysiology. We possess a large skill-set and toolkit to answer a variety of experimental questions including optogentics, chemogenetics, behavioural paradigms (stress), immunohistochemisty, stereotaxic and other recoverable surgeries that frame our synaptic studies within a larger context.

All Projects by this Lab

Inhibitory mechanisms within the nucleus of the solitary tractSynaptic gating of viscerosensory signalsViscerosensory pathways in the brainUtilising insect peptide hormones in the mammalian nervous systemNext generation vagal nerve stimulation

Systems Neurophysiology

In Systems Neurophysiology we seek to learn how the nervous system controls various bodily functions and how that control is altered in disease. Our disease focus includes not only neurological disorders such as epilepsy and multiple sclerosis, but also how the nervous system impacts on non-neurological diseases such as heart failure and inflammatory diseases.  A clear understanding of basic mechanisms is crucial in developing better therapies and reducing the impacts of illness. 

All Labs that operate in this Division

Autonomic Neuroscience LaboratoryDigestive Physiology and Nutrition LaboratoryNeurocardiovascular LaboratoryNeurovascular Biology LaboratoryRespiratory Neurophysiology LaboratoryViscerosensory Laboratory