Neurotensin receptor 2 (NTS2) is one of three receptors that mediate the effects of the tridecapeptide neurotensin. Neurotensin is synthesized and secreted from neurons in the central neural system (CNS) and from endocrine cells in the gastrointestinal tract.nNeurotensin receptor 2 (NTS2) is one of three receptors that mediate the effects of the tridecapeptide neurotensin. Neurotensin is synthesized and secreted from neurons in the central neural system (CNS) and from endocrine cells in the gastrointestinal tract.