Why does repeated use of certain recreational drugs lead to downregulation of neurotransmitter receptors in the brain?

💡 Explanation

Prolonged exposure to certain drugs causes a compensatory downregulation of neurotransmitter receptors via endocytosis, because the postsynaptic cell attempts to maintain homeostasis by reducing its sensitivity to excessive stimulation. Therefore, receptor internalization occurs, rather than receptor degradation or autoimmune response.

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