PERIPHERAL N-METHYLASPARTATE RECEPTORS IN CARDIOVASCULAR DISEASES AND DIABETES MELLITUS

Glutamate is the dominant excitatory amino acid mediator in the central nervous system and its receptors are divided into metabotropic and ionotropic receptors. N-methylaspartate (NMDA) receptors are a member of the ionotropic glutamate receptor family and these receptors are transmembrane ion channels with 7 different subunits. Depending on their subunit components and signal proteins NMDA receptors play a role in long-term potentiation or depression, stimulation or inhibition of neurotransmitter release, and cell survival or death. NMDA receptors are predominantly expressed in neurons. Recently, it has been shown that NMDA receptors are expressed in non-neuronal cells and peripheral tissues in the central nervous system and the distribution of these receptors outside the central nervous system has emerged as an interesting topic. Recent findings suggest that NMDA receptors may he present in multiple cells and tissues including pancreatic islet cells, heart, lung, medulla, kidneys. Non-neuronal NMDA receptors play an important role in proliferation, apoptosis, cell adhesion and migration, actin rearrangement, cell growth and differentiation, and regulation of hormone secretion and non-neuronal NMDA receptors may be involved in wound healing, insulin secretion, blood-brain barrier integrity, and myelination. In this review, the role of the NMDA receptors in the heart and pancreas is discussed and the therapeutic potential of these receptors in cardiovascular and diabetic diseases has been evaluated. New treatment options for chronic diseases can he provided by further investigation of non-neuronal NMDA receptors.