Evolutionarily conserved differences in pallial and thalamic short-term synaptic plasticity in striatum.

Area of Science:

• Neuroscience
• Comparative Neurobiology
• Molecular and Cellular Neuroscience

Background:

• The basal ganglia, including the striatum, are evolutionarily conserved across vertebrates.
• Lamprey striatal afferent organization mirrors mammalian pathways, with key inputs from the thalamus (Th) and lateral pallium (LPal).

Purpose of the Study:

• To investigate the pharmacology and synaptic dynamics of LPal and Th afferent inputs onto lamprey striatal neurons.
• To elucidate information processing within the lamprey striatum.

Main Methods:

• Whole-cell current-clamp recordings in acute brain slices.
• Preservation of Th and LPal afferent fibres.
• Tract tracing and immunohistochemistry.

Main Results:

• Th and LPal provide monosynaptic glutamatergic input via NMDA and AMPA receptors.
• LPal input shows short-term facilitation, while Th input exhibits short-term synaptic depression.
• Both inputs recruit activity-dependent intrastriatal oligosynaptic inhibition.

Conclusions:

• Lamprey striatal inputs display differential short-term synaptic plasticity.
• These plasticity differences between Th and LPal (cortical homologue) inputs are conserved in mammals, indicating an ancient evolutionary trait.