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Updated: May 24, 2026

Double-barreled and Concentric Microelectrodes for Measurement of Extracellular Ion Signals in Brain Tissue
Published on: September 5, 2015
Synergistic interactions between kainate and mGlu receptors regulate bouton Ca signalling and mossy fibre LTP
Robert Nisticò1, Sheila L Dargan, Mascia Amici
1MRC Centre for Synaptic Plasticity, School of Physiology and Pharmacology, University of Bristol, Bristol, BS8 1TD, United Kingdom.
Abstract:
It is currently unknown why glutamatergic presynaptic terminals express multiple types of glutamate receptors. We have addressed this question by studying both acute and long-term regulation of mossy fibre function in the hippocampus. We find that inhibition of both mGlu₁ and mGlu₅ receptors together can block the induction of mossy fibre LTP. Furthermore, mossy fibre LTP can be induced by the pharmacological activation of either mGlu₁ or mGlu₅ receptors, provided that kainate receptors are also stimulated. Like conventional mossy fibre LTP, chemically-induced mossy fibre LTP (chem-LTPm) depends on Ca²⁺ release from intracellular stores and the activation of PKA. Similar synergistic interactions between mGlu receptors and kainate receptors were observed at the level of Ca²⁺ signalling in individual giant mossy fibre boutons. Thus three distinct glutamate receptors interact, in both an AND and OR gate fashion, to regulate both immediate and long-term presynaptic function in the brain.
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