The alpha-2A adrenergic receptor (α_2A adrenoceptor), also known as ADRA2A, is an α₂-adrenergic receptor, and also denotes the

human gene Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are great apes characterized by their hairlessness, bipedalism, and high intelligenc ...

encoding it.

Receptor

α₂-adrenergic receptors include 3 highly homologous subtypes: α_2A, α_2B, and α_2C. These receptors have a critical role in regulating

neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotra ...

release from

sympathetic nerves The sympathetic nervous system (SNS or SANS, sympathetic autonomic nervous system, to differentiate it from the somatic nervous system) is one of the three divisions of the autonomic nervous system, the others being the parasympathetic nervous sy ...

and from adrenergic neurons in the

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...

. Studies in mice revealed that both the α_2A and α_2C subtypes were required for normal

presynaptic In the nervous system, a synapse is a structure that allows a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or a target effector cell. Synapses can be classified as either chemical or electrical, depending o ...

control of transmitter release from sympathetic nerves in the

heart The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...

and from central noradrenergic neurons; the α_2A subtype inhibited transmitter release at high stimulation frequencies, whereas the α_2C subtype modulated neurotransmission at lower levels of nerve activity.

Gene

This gene encodes α_2A subtype and it contains no

introns An intron is any Nucleic acid sequence, nucleotide sequence within a gene that is not expressed or operative in the final RNA product. The word ''intron'' is derived from the term ''intragenic region'', i.e., a region inside a gene."The notion of ...

in either its coding or untranslated sequences.

Ligands

Agonists

* 4-NEMD *

Brimonidine Brimonidine is an α2 agonist medication used to treat open-angle glaucoma, ocular hypertension, and rosacea. In rosacea it improves the redness. It is used as eye drops or applied to the skin. It is also available in the fixed-dose combinatio ...

Clonidine Clonidine, sold under the brand name Catapres among others, is an α2A-adrenergic receptor agonist medication used to treat high blood pressure, attention deficit hyperactivity disorder (ADHD), drug withdrawal (e.g., alcohol, opioids, or nic ...

Detomidine Detomidine is an imidazole derivative and Alpha-2 adrenergic receptor, α2-adrenergic receptor agonist, used as a large animal sedative, primarily used in horses. It is usually available as the salt (chemistry), salt detomidine hydrochloride. It ...

Dexmedetomidine Dexmedetomidine, sold under the brand name Precedex among others, is a medication used for sedation. Veterinarians use dexmedetomidine for similar purposes in treating cats, dogs, and horses. It is also used in humans to treat acute agitation as ...

Guanfacine Guanfacine, sold under the brand name Tenex ( immediate-release) and Intuniv ( extended-release) among others, is an oral alpha-2a agonist medication used to treat attention deficit hyperactivity disorder (ADHD) and high blood pressure. Co ...

Lofexidine Lofexidine, sold under the brand name Lucemyra among others, is a medication historically used to treat high blood pressure; today, it is more commonly used to help with the physical symptoms of opioid withdrawal. It is taken by mouth. It is an ...

Myrcene Myrcene, or β-myrcene, is a terpene, monoterpene. A colorless oil, it occurs widely in essential oils. It is produced mainly semi-synthetically from ''Myrcia'', from which it gets its name. It is an intermediate in the production of several frag ...

Medetomidine Medetomidine is a veterinary anesthetic drug with potent sedative effects and emerging illicit drug adulterant. It is a racemic mixture of two stereoisomers, levomedetomidine and dexmedetomidine, the latter being the isomer with the pharmac ...

* PS75 *

Tizanidine Tizanidine, sold under the brand name Zanaflex among others, is an alpha-2 (α2) adrenergic receptor agonist, similar to clonidine, that is used to treat muscle spasticity due to spinal cord injury, multiple sclerosis, and spastic cerebral ...

Xylazine Xylazine is a structural analog of clonidine and an α2-adrenergic receptor, α2-adrenergic receptor agonist, sold under many trade names worldwide, most notably the Bayer brand name Rompun, as well as Anased, Sedazine and Chanazine. Xylazine ...

Antagonists

* Atipamezole *

Idazoxan Idazoxan (INN) is a drug which is used in scientific research. It acts as both a selective α2-adrenergic receptor antagonist, and an antagonist for the imidazoline receptor. Idazoxan has been under investigation as an antidepressant, but it di ...

* 1-PP (active metabolite of

buspirone Buspirone, sold under the brand name Buspar among others, is an anxiolytic, a medication primarily used to treat anxiety disorders, particularly generalized anxiety disorder (GAD). It is a serotonin 5-HT1A receptor, 5-HT1A receptor partial ag ...

and gepirone) *

Asenapine Asenapine, sold under the brand name Saphris among others, is an atypical antipsychotic medication used to treat schizophrenia and acute mania associated with bipolar disorder as well as the medium to long-term management of bipolar disorder. I ...

* BRL-44408 *

Clozapine Clozapine, sold under the brand name Clozaril among others, is a psychiatric medication and was the first atypical antipsychotic to be discovered. It is used primarily to treat people with schizophrenia and schizoaffective disorder who have ...

* Lurasidone *

Mianserin Mianserin, sold under the brand name Tolvon among others, is an atypical antidepressant that is used primarily in the treatment of depression in Europe and elsewhere in the world. It is a tetracyclic antidepressant (TeCA). Mianserin is closel ...

Mirtazapine Mirtazapine, sold under the brand name Remeron among others, is an atypical antidepressant, atypical tetracyclic antidepressant, and as such is used primarily to treat Depression (mood), depression. Its effects may take up to four weeks but ca ...

* Paliperidone *

Risperidone Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder, as well as aggressive and self-injurious behaviors associated with autism spectrum disorder. It is t ...

Yohimbine Yohimbine, also known as quebrachine, is an indole alkaloid derived from the bark of the African tree '' Pausinystalia johimbe'' (yohimbe); also from the bark of the unrelated South American tree '' Aspidosperma quebracho-blanco''. Yohimbine is ...

References

External links

* * * Adrenergic receptors Biology of attention deficit hyperactivity disorder {{transmembranereceptor-stub