My watch list
my.chemeurope.com  
Login  

GABAB receptor



gamma-aminobutyric acid (GABA) B receptor, 1
Identifiers
Symbol GABBR1
Entrez 2550
HUGO 4070
OMIM 603540
RefSeq NM_021905
UniProt Q9UBS5
Other data
Locus Chr. 6 p21.3
gamma-aminobutyric acid (GABA) B receptor, 2
Identifiers
Symbol GABBR2
Alt. Symbols GPR51
Entrez 9568
HUGO 4507
OMIM 607340
RefSeq NM_005458
UniProt O75899
Other data
Locus Chr. 9 q22.1-22.3

GABAB receptors (GABABR) are metabotropic transmembrane receptors for gamma-aminobutyric acid (GABA) that are linked via G-proteins to potassium channels.[1] These receptors are found in the central and peripheral autonomic nervous system.[2]

Additional recommended knowledge

Contents

Functions

They can stimulate the opening of K+ channels which brings the neuron closer to the equilibrium potential of K+, hyperpolarising the neuron. This prevents sodium channels from opening, action potentials from firing, and VDCCs from opening, and so stops neurotransmitter release. Thus GABAB receptors are considered inhibitory receptors.

GABAB receptors can also reduce the activity of adenylyl cyclase and decrease the cell’s conductance to Ca2+.[2]

GABAB receptors are involved in behavioral actions of ethanol, [3] gamma-Hydroxybutyric acid (GHB),[4] and possibly in pain.[5] Recent research suggests that these receptors may play an important developmental role. [6]

Structure

GABABRs are similar in structure to and in the same receptor family with metabotropic glutamate receptors.[7] There are two subtypes of the receptor, GABAB1 and GABAB2,[8][2] and these appear to assemble as heterodimers in neuronal membranes by linking up by their intracellular C termini.[2][7]

It is speculated that binding of GABA causes the subunits to swing shut around the agonist like a venus fly trap.[2]

Agonists and antagonists

    Baclofen is a GABA analogue which acts as a selective agonist of GABAB receptors, and is used as a muscle relaxant. However, it can aggravate absence seizures, and so is not used in epilepsy.

Saclofen, phaclofen and SCH-50911 are selective GABAB antagonists.

See also

References

  1. ^ Chen K, Li H, Ye N, Zhang J, Wang J (2005). "Role of GABAB receptors in GABA and baclofen-induced inhibition of adult rat cerebellar interpositus nucleus neurons in vitro". Brain Res Bull 67 (4): 310-8. PMID 16182939.
  2. ^ a b c d e Martin I.L., and Dunn S.M.J. 2002. GABA receptors Tocris Cookson Ltd.
  3. ^ Dzitoyeva S, Dimitrijevic N, Manev H (2003). "Gamma-aminobutyric acid B receptor 1 mediates behavior-impairing actions of alcohol in Drosophila: adult RNA interference and pharmacological evidence". Proc Natl Acad Sci U S A 100 (9): 5485-90. PMID 12692303.
  4. ^ Dimitrijevic N, Dzitoyeva S, Satta R, Imbesi M, Yildiz S, Manev H (2005). "Drosophila GABA(B) receptors are involved in behavioral effects of gamma-hydroxybutyric acid (GHB)". Eur J Pharmacol 519 (3): 246-52. PMID 16129424.
  5. ^ Manev H, Dimitrijevic N (2004). "Drosophila model for in vivo pharmacological analgesia research". Eur J Pharmacol 491 (2-3): 207-8. PMID 15140638.
  6. ^ Dzitoyeva S, Gutnov A, Imbesi M, Dimitrijevic N, Manev H (2005). "Developmental role of GABAB(1) receptors in Drosophila". Brain Res Dev Brain Res 158 (1-2): 111-4. PMID 16054235.
  7. ^ a b MRC (Medical Research Counsil). 2003. Glutamate receptors: Structures and functions. University of Brisotol Centre for Synaptic Plasticity.
  8. ^ Purves D., Augustine G.J., Fitzpatrick D., Katz L.C., LaMantia A.S., McNamara J.O., and Williams S.M. 2001. Neuroscience, Second Edition. Sinauer Associates, Inc.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "GABAB_receptor". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE