Which mechanism explains why prolonged stimulation of a neuron by a specific neurotransmitter can lead to receptor desensitization?

💡 Explanation

Prolonged stimulation often results in receptor desensitization due to receptor endocytosis, a process where the cell membrane invaginates and internalizes the receptor, reducing the number of receptors on the cell surface. This reduces the neuron's response to the neurotransmitter because there are fewer available receptors, therefore, endocytosis causes desensitization, rather than altered synthesis or gene expression which could enhance sensitivity.

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