[Pathophysiology of the glutamate and the glycine transporters: new therapeutic targets].

INTRODUCTION: The amino acids glutamate and glycine, apart from their role in protein synthesis, are two fundamental neurotransmitters in the central nervous system of mammals. The first one is ubiquitous and is involved in excitatory pathways of the neocortex, the retina and the cerebellum, and the second is involved in inhibitory pathways of brain caudal areas. However, both share their way of acting by integrating into the functioning of glutamate receptors of the NMDA type fundamentals in the regulation of motor, sensory and cognitive systems. AIM: To highlight the need for a fine regulation of glutamate and glycine concentrations in the intracellular and extracellular spaces of the nervous system through the action of very specific transporters for both neurotransmitters located in the plasma membrane of neurons and glial cells. DEVELOPMENT: The role of the glutamate and glycine transporters in glutamatergic and glycinergic neurotransmission and in the functioning of the nervous system is described. The pathological consequences of imbalances in these signaling pathways are pointed out. We also describe its involvement in pathologies such as schizophrenia, chronic pain, cerebral ischemia, diseases such as hereditary hyperekplexia and the non-ketotic hyperglycinemia, and neurodegenerative disorders. CONCLUSIONS: The knowledge at molecular level of the way of acting of these transporters for glutamate and glycine is allowing the identification and development of new therapeutic strategies for pathologies such as those described above and the development of new drugs.