Metabotropic Glutamate Receptors do not Impact Post-Tetanic Plasticity at the Crayfish Neuromuscular Junction

Abstract

It has been suggested that metabotropic Glutamate receptors (mGluRs) play a role in reducing the symptoms of Schizophrenia. To further understand this disease and how mGluRs function, we studied the effects of group II and group III mGluRs on post-tetanic plasticity at the crayfish neuromuscular junction using intracellular recording. The crayfish tail was immersed in either a standard saline solution, a group II mGluR antagonist saline solution, or a group III mGluR antagonist saline solution. We expected that the addition of these antagonists would result in the inhibition of post-tetanic plasticity and a decrease in the amplitude of excitatory postsynaptic potentials (EPSPs) after stimulating the neurons at a high frequency, expecting that the group II antagonist would have the greater effect. However, our results showed no significant change in the difference between EPSP amplitude before and after the high frequency stimulation when the drugs were administered in relation to the control. This led us to conclude that mGluRs are not an influential player in creating post-tetanic plasticity in crayfish.