What is receptor desensitization?

What is receptor desensitization?

• A. Increased receptor activity following ligand binding
• B. Reduction in receptor response after prolonged exposure to ligand
• C. A process that permanently activates receptors
• D. The internalization of receptors upon initial activation

Answer: (B)

Receptor desensitization refers to the phenomenon where a receptor's response diminishes after prolonged exposure to its ligand. When a receptor is continuously stimulated by a ligand, it may undergo conformational changes that result in decreased signaling efficacy or overall activity. This can happen through various mechanisms such as receptor phosphorylation, which can lead to a reduced affinity for the ligand or the recruitment of inhibitory proteins that further dampen the response. The purpose of this process is to prevent overstimulation of the cell and maintain homeostasis, ensuring that cellular responses are regulated appropriately to avoid potential damage from prolonged activation. In contrast, the other options describe processes that do not accurately capture the essence of receptor desensitization. For instance, increased receptor activity following ligand binding is not characteristic of desensitization; instead, it relates to receptor activation. Permanently activating receptors does not align with the temporary and adaptive nature of desensitization, which is typically reversible. Finally, while the internalization of receptors can be a mechanism associated with desensitization, it isn't synonymous with the term itself, as desensitization primarily refers to reduced responsiveness rather than the physical relocation of the receptor.

Receptor desensitization refers to the phenomenon where a receptor's response diminishes after prolonged exposure to its ligand. When a receptor is continuously stimulated by a ligand, it may undergo conformational changes that result in decreased signaling efficacy or overall activity. This can happen through various mechanisms such as receptor phosphorylation, which can lead to a reduced affinity for the ligand or the recruitment of inhibitory proteins that further dampen the response. The purpose of this process is to prevent overstimulation of the cell and maintain homeostasis, ensuring that cellular responses are regulated appropriately to avoid potential damage from prolonged activation.

In contrast, the other options describe processes that do not accurately capture the essence of receptor desensitization. For instance, increased receptor activity following ligand binding is not characteristic of desensitization; instead, it relates to receptor activation. Permanently activating receptors does not align with the temporary and adaptive nature of desensitization, which is typically reversible. Finally, while the internalization of receptors can be a mechanism associated with desensitization, it isn't synonymous with the term itself, as desensitization primarily refers to reduced responsiveness rather than the physical relocation of the receptor.