Glial modulation of neuronal activity

Astrocytes are the glial cells that surround neurons in the central nervous system and perform a variety of roles to support neurotransmission. The aim of this project is to understand the ways in which astrocytes can sense the activity at adjacent synapses and how in-turn they can release substances that modulate these synapses.

One of the vital roles that astrocytes play in neurotransmission is to take-up the neurotransmitter glutamate, thus removing it from the synaptic cleft and terminating the synaptic signal. Following this, they are thought to metabolise this glutamate and subsequently secrete molecules that can be used by neurons to re-generate the released glutamate. Part of this project is aimed at understanding how astrocytes release these molecules and what cellular mechanisms regulate these processes. Finally, we wish to understand how, via this mechanism, astrocytes can ultimately control the strength of neurotransmission at neighbouring synapses.

Astrocyte activation is assessed by using patch-clamp recording of electrical signals or fluorescent imaging of ion changes (e.g. pH, Na+ or Ca2+). Similarly, the effects of astrocytic on synaptic transmission is studied using electrical and fluorescent recordings from adjacent neurons.