Question

What are the six classical neurotransmitters and their major receptor types?

Answer 1

Answer.

1. Dopamine
Dopamine Receptors
• There are five types of dopamine receptors.D1,D2,D3,D4,D5.These can be divided into two main subtypes:
> D1 like receptor family: the Gs protein is involved and adenylyl cyclase would be activated. The action of the enzyme causes the conversion of adenosine triphosphate to cyclic adenosine monophosphate (cAMP).
>D2 like receptor family: which is the receptor combining with the Gi protein and its activated alpha- subunit then inhibits adenylyl cyclase so that the concentration of cAMP is reduced.

2. Endorphins
According to their selectivity, the receptors for endorphins are classified as: μ, δ, κ, ɛ and σ. There are three subtypes of μ (μ1-3) and two of δ (δ1-2) according to the different degrees of selectivity. The μ receptors bind morphine, δ receptors enkephalins, κ receptors dynorphin and ε receptors β-endorphin.

3. Serotonin
5-hydroxytryptamine receptors or 5-HT receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems.

4. GABA
There are two classes of GABA receptors: GABAA and GABAB. GABAA receptors are ligand-gated ion channels (also known as ionotropic receptors); whereas GABAB receptors are G protein-coupled receptors, also called metabotropic receptors.

5. Acetylcholine
There are two types of acetylcholine receptors (AChR) that bind acetylcholine and transmit its signal: muscarinic AChRs and nicotinic AChRs, which are named after the agonists muscarine and nicotine, respectively.

6. Glutamate
Several types of ionotropic glutamate receptors have been identified. Three of these are ligand-gated ion channels called NMDA receptors, AMPA receptors, and kainate receptors