Neurotransmitter receptors are expressed on the surface of post-synaptic cells to bind ligand-specific neurotransmitters and hormones. They are also expressed on presynaptic cells to provide feedback mechanisms and attenuate excessive neurotransmitter release. The majority of neurotransmitter receptors are integral membrane proteins with seven transmembrane domains, commonly coupled to G-proteins. Binding of a ligand to its specific neurotransmitter receptor may result in the activation of a myriad of cell signal transduction pathways and modulation of ion channel homeostasis. R&D Systems offers quality products for experiments focused on the role of dopamine, gamma-aminobutyric acid (GABA), glutamate, N-methyl-D-aspartic acid (NMDA), thrombin and more.