Orexin receptor type 1 (Ox1R or OX₁), also known as hypocretin receptor type 1 (HcrtR1), is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

that in humans is encoded by the HCRTR1

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

Function

The orexin 1 receptor (OX₁), is a

G-protein coupled receptor G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large protein family, group of evoluti ...

that is heavily expressed in projections from the

lateral hypothalamus The lateral hypothalamus (LH), also called the lateral hypothalamic area (LHA), contains the primary orexinergic nucleus within the hypothalamus that widely projects throughout the nervous system; this system of neurons mediates an array of cogni ...

and is involved in the regulation of feeding behaviour. OX₁ selectively binds the

orexin-A Orexin-A, also known as hypocretin-1, is a naturally occurring neuropeptide and orexin isoform. The orexinergic nucleus in the lateral hypothalamus is the primary orexin projection system in the brain. Structure Orexin-A is a peptide composed of ...

neuropeptide. It shares 64% identity with OX₂.

Ligands

Agonists

Orexin-A Orexin-A, also known as hypocretin-1, is a naturally occurring neuropeptide and orexin isoform. The orexinergic nucleus in the lateral hypothalamus is the primary orexin projection system in the brain. Structure Orexin-A is a peptide composed of ...

Antagonists

* RTIOX-276 - Selective OX₁ antagonist * ACT-335827 - Selective OX₁ antagonist *

Almorexant Almorexant (INN), also known by its development code ACT-078573, is an orexin antagonist, acting as a competitive antagonist of the OX1 and OX2 orexin receptors, which was being developed by the pharmaceutical companies Actelion and GSK for ...

- Dual OX₁ and OX₂

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Lemborexant Lemborexant, sold under the brand name Dayvigo, is an orexin antagonist medication which is used in the treatment of insomnia. It is indicated specifically for the treatment of insomnia characterized by difficulties with sleep onset and/or ma ...

- Dual OX₁ and OX₂

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Nemorexant Daridorexant, sold under the brand name Quviviq, is an orexin antagonist medication which is used for the treatment of insomnia. Daridorexant is taken by mouth. Side effects of daridorexant include headache, somnolence, and fatigue. The medi ...

- Dual OX₁ and OX₂ antagonist * SB-334,867 - Selective OX₁ antagonist * SB-408,124 - Selective OX₁ antagonist * SB-649,868 - Dual OX₁ and OX₂

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Suvorexant Suvorexant, sold under the brand name Belsomra, is an orexin antagonist medication which is used in the treatment of insomnia. It is indicated specifically for the treatment of insomnia characterized by difficulties with sleep onset and/or ma ...

- Dual OX₁ and OX₂

antagonist An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.Orexin receptor The orexin receptor (also referred to as the hypocretin receptor) is a G-protein-coupled receptor that binds the neuropeptide orexin. There are two variants, OX1 and OX2, each encoded by a different gene (, ). Both orexin receptors exhibit ...

Function

Ligands

Agonists

Antagonists

References

External links

Further reading