The alpha-1A adrenergic receptor (α_1A adrenoreceptor), also known as ADRA1A, formerly known also as the alpha-1C adrenergic receptor, is an

alpha-1 adrenergic receptor alpha-1 (α1) adrenergic receptors are G protein-coupled receptors (GPCRs) associated with the Gq heterotrimeric G protein. α1-adrenergic receptors are subdivided into three highly homologous subtypes, i.e., α1A-, α1B-, and α1D-adrenergic ...

, and also denotes the human

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

encoding it. There is no longer a subtype α_1C receptor. At one time, there was a subtype known as α_1C, but it was found to be identical to the previously discovered α_1A receptor subtype. To avoid confusion, the naming convention was continued with the letter D.

Receptor

There are 3 alpha-1 adrenergic receptor subtypes: alpha-1A, -1B and -1D, all of which signal through the Gq/11 family of G-proteins. Different subtypes show different patterns of activation. The majority of alpha-1 receptors are directed toward the function of epinephrine, a hormone that has to do with the

fight-or-flight response The fight-or-flight or the fight-flight-or-freeze response (also called hyperarousal or the acute stress response) is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It was first des ...

Gene

This gene encodes the alpha-1A-adrenergic receptor. Alternative splicing of this gene generates four transcript variants, which encode four different isoforms with distinct C-termini but having similar ligand binding properties.

Ligands

Agonists

* 6-(5-fluoro-2-pyrimidin-5-yl-phenyl)-6,7-dihydro-5H-pyrrolo ,2-amidazole: EC₅₀ = 1nM, E_max = 65%; good selectivity over α1B, α1D and α2A subtypes * further partial agonistic imidazole compounds * A-61603 *

Metaraminol Metaraminol, previously sold under the brand name Aramine among others and also known as metaradrine, is a stereoisomer of ''meta''-hydroxynorephedrine (3,β-dihydroxyamphetamine), is a potent sympathomimetic amine used in the prevention and tr ...

Antagonists

Tamsulosin Tamsulosin, sold under the brand name Flomax among others, is a medication used to treat symptomatic benign prostatic hyperplasia (BPH) and chronic prostatitis and to help with the passage of kidney stones. The evidence for benefit with a ki ...

: for treatment of

benign prostatic hyperplasia Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss o ...

Silodosin Silodosin (known by the trade names Silosoft in India, Urief in Japan, Rapaflo in North America, and Silodyx or Niksol in the European Union) is a medication for the symptomatic treatment of benign prostatic hyperplasia (BPH). It acts as an α1- ...

: for treatment of

Doxazosin Doxazosin, sold under the brand names Cardura among others, is a medication used to treat symptoms of benign prostatic hyperplasia (enlarged prostate) and hypertension (high blood pressure). For high blood pressure, it is a less preferred option. ...

: for treatment of

and/or

Hypertension Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...

Risperidone Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It is taken either by mouth or by injection (subcutaneous or intramuscular). The injectable versions ...

: used to treat

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social withdra ...

and

bipolar disorder Bipolar disorder, previously known as manic depression, is a mental disorder characterized by periods of depression and periods of abnormally elevated mood that last from days to weeks each. If the elevated mood is severe or associated with ...

* WB-4101 *

Ziprasidone Ziprasidone, sold under the brand name Geodon among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It may be used by mouth and by injection into a muscle (IM). The IM form may be used for acute agitation ...

* Most

Tricyclic antidepressant Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...

Role in neural circuits

α1A-adrenergic receptor subtypes increase inhibition at dendrodendritic synapses, suggesting a synaptic mechanism for noradrenergic modulation of olfactory driven behaviors.

References

External links

* *

Receptor

Gene

Ligands

Agonists

Antagonists

Role in neural circuits

See also

References

External links

Further reading