What distinguishes the effect of chronic opioid use from acute use on neuronal activity within the nucleus accumbens?

💡 Explanation

Chronic opioid use leads to a downregulation of dopamine receptor sensitivity in the nucleus accumbens through receptor internalization, because the brain attempts to maintain homeostasis. Therefore, tolerance develops, rather than an acute increase in dopamine release or alteration in other neurotransmitter systems like GABA or glutamate alone.

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