Jennings Lab ~ Current Projects

Project 1: Immunohistochemical localisation NMDA receptor subunits in trigeminal ganglion neurons innervating the dura.

The NMDA receptor has long been associated with long-term changes in neuronal function and has been implicated in a variety of brain processes (eg. pain and memory).  The subunit composition of the receptor is one of the factors that determine kinetic (functional) properties of the receptor.  The aim of this project is to determine the NR2 subunit composition of the NMDA receptors in trigeminal ganglion cells innervating specific targets.  

Project 2:  The role of pre-synaptic NMDA receptors in modulating synaptic transmission in the medullary dorsal horn.

Trigeminal primary afferent nerves synapse onto cells in the spinal trigeminal nucleus (also referred to as the medullary dorsal horn).  The aim of this project is to examine the role of presynaptic NMDA receptors in modulating synaptic transmission at this site. This project builds on previous results from the laboratory and uses whole-cell patch clamp electrophysiology in a brainstem slice preparation.

Project 3: Ion channels involved in determining the excitability of sensory neurons.

The excitability of primary afferent nerves is partly determined by a range of ion channels that determine resting membrane potential.  This project will examine ion channel function in the cell bodies of sensory nerves mediating trigeminal pain using whole-cell patch-clamp electrophysiology.  This allows the measurement of membrane currents produced in response to the opening of ion channels following receptor activation.  A combination of voltage step protocols and pharmacology will allow full characterisation of the channels involved.  Changes in channel expression or function in injury states, is likely to be reflected in changes in neuronal excitability.