Role of different subtypes of dopamine receptors in response to acute opiate withdrawal.

Abstract

•Those experiencing withdrawal from drugs of abuse display negative emotional symptoms such as anxiety. Anxiety during withdrawal from an acute opiate exposure also causes potentiation of the acoustic startle reflex (“withdrawal-potentiated startle”).2,4,5 •Experiments in the Gewirtz lab with a general dopamine receptor agonist, apomorphine have suggested that anxiety during acute withdrawal from opioidsis mediated by levels of dopamine in the brain. •While we know dopamine is important in this phenomena we do not know which dopamine receptors play a role in producing anxiety symptoms. •There are five subtypes of dopamine subunits that are classified in two populations: D1-like and D2-like receptors. Both have been shown to play a role in producing withdrawal symptoms. 1,3 •Our goal is to discover which receptor family plays a role in producing withdrawal-potentiated startle. We will test this by administering either a D1-like agonist or D2-like agonist, or both in a cocktail with the expectation that withdrawal potentiated startle will be blocked in the groups that are important for producing anxiety.