D2 receptor antagonist

A D2 receptor antagonist prevents the activation of the dopamine D2 receptor. The D2 receptor is coupled to inhibitory G-proteins, which dissociate from the receptor on agonist binding and inhibit secondary messenger signaling mechanisms. This causes inhibition of down-stream signaling mechanisms. Antagonist binding inhibits this usual process, resulting in cell depolarisation.

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References

How drugs act: molecular aspects. In: Pharmacology, 4^th edition. Rang HP, Dale MM and Ritter JM. Edinburgh, UK: Harcourt Publishers Ltd, 2001:2–46.

Other peripheral mediators: 5-hydroxytryptamine and purines. In: Pharmacology, 4^th edition. Rang HP, Dale MM and Ritter JM. Edinburgh, UK: Harcourt Publishers Ltd, 2001:539–49.