The effects of a Group III metabotropic glutamate receptor antagonist at the crayfish neuromuscular junction

Abstract

This experiment sought to obtain information about the role of metabotropic glutamate receptors (mGluR) in higher brain function. The study particularly looked to verify the presence of group III metabotropic glutamate receptors at the crayfish neuromuscular junction, analogous to a synapse of the human brain, through the use of a group III specific antagonist. Measurements compared in the presence of normal crayfish saline and saline solutions with different concentrations of the antagonist added, where a significant change in amplitude of the EPSPs would indicate the antagonist was interacting with mGluRs present in the presynaptic or postsynaptic cell. When comparing the results of the study in the control solution to the antagonist modified solution data showed no significant decrease in the mean amplitude of elicited EPSPs, but did show a significant increase in the mean lowest voltage needed to elicit an EPSP. The latter suggests the antagonist was operating, and thus that mGluRs were present in the cell; however, the results of the study are not conclusive enough to demonstrate that metabotropic glutamate receptors of group III are present in the crayfish neuromuscular junction.