NTR1

Neurotensin receptor 1 (NTR1, also known as NTSR1) is a high-affinity G protein-coupled receptor that mediates the biological actions of the neuropeptide neurotensin in both the central nervous system and peripheral tissues^[1][2]. Mechanistically, NTR1 activation induces receptor conformational changes that promote coupling to G proteins and β-arrestins, thereby regulating downstream signaling pathways involved in neuronal activity, cellular proliferation, and physiological homeostasis^[2][3]. Through these signaling mechanisms, NTR1 contributes to the regulation of dopaminergic neurotransmission and has become an important experimental target in studies of neuropsychiatric disorders and addiction-related behaviors^[4]. In disease-associated contexts, elevated NTR1 expression has been reported in several malignancies, and neurotensin-dependent signaling can engage oncogenic pathways including PKC/ERK and AKT, supporting investigation of NTR1 in cancer biology models^[5]. Compared with related neurotensin receptor isoforms, NTR1 displays high affinity for neurotensin, whereas NTR2 exhibits lower affinity and distinct pharmacological recognition characteristics, indicating functional and pharmacological differentiation within the receptor family^[6]. For experimental applications, diverse peptide and small-molecule modulators have been developed to interrogate NTR1 signaling, including agonists, antagonists, and biased ligands that selectively influence G-protein- or β-arrestin-associated responses^[3][4]. These pharmacological tools facilitate mechanistic studies of receptor activation, signaling bias, and disease-relevant pathway regulation^[3][4].