Role of Metabotropic Glutamate Receptors in Alcohol-Drinking Behaviors

Abstract

Glutamatergic system impairments have been associated with long-term use of drugs of abuse, including alcohol. Metabotropic glutamate receptors (mGlus) have been suggested to be involved in drug addiction and other neuropsychiatric disorders. Different subtypes of mGlus have been considered to be implicated in certain neuropsychiatric disorders, including substance use disorders. Chronic uses of these drugs have been found to alter the function and expression of mGlus. For example, increases in mGlu1 expression in the nucleus accumbens (NAc) were found in animals exposed to either alcohol or nicotine. However, the expression of mGlu2/3 is decreased in the NAc following chronic exposure to alcohol. Importantly, pharmacological studies showed that mGlu1/5 antagonists and mGlu2/3 agonists attenuated alcohol intake and relapse-like alcohol-drinking behaviors. Furthermore, new technologies, such as optogenetics, have been used to investigate the regulatory roles of mGlu isoforms in the mesocorticolimbic brain areas in animals exposed to alcohol. In this book chapter, we discussed the effects of alcohol exposure using different drinking paradigms on the expression and function of mGlus and the pharmacological manipulations (via agonists or antagonists) of mGlus in alcohol-seeking and relapse to alcohol-like behaviors.