Neurotensin and Neurotensin Receptors in health and diseases: A brief review

Neurotensin (NT), a thirteen amino acid peptide is located primarily in the brain/central nervous system (CNS) and intestine. In brain or CNS, NT acts as a neurotransmitter/neuromodulator whereas in the digestive or gastrointestinal (GI) tract it works like a hormone. The peptide is processed differentially from its precursor in CNS and GI tissues. As a neuromodulator it controls several neuronal actions influencing dopaminergic, GABAergic, serotonergic, glutaminergic and cholinergic neurons. The peptide has a significant role in Schizophrenia, Parkinson disorder, Alzheimers disease, pain/analgesia, eating disorder, tumor growth and inflammation. It also exerts its influences by interacting with itscorresponding receptors. Until now three types of NT receptors (NTR- 1, NTR-2 and NTR-3) are identified for most physiologic effects. Among them, NTR-1 and NTR-2 are the typical G-protein coupled receptors (GPCR) with seven transmembrane (7TM) spanning the cell surface bi-layer whereas NTR-3 is a single transmembrane receptor belonging to the Sortilin family. The recent attention relating to NT-NTR interactions is drawn for several of its important physiologic role in health and diseases. Among them, neurological, analgesic and malignancy are considered to be the major concern.