Receptor Downregulation
Definition
A reduction in the number or availability of receptors in a cell or at its surface. It is one possible mechanism of reduced responsiveness to a signal.
By PurePeptideHub Editorial Team · Updated . Educational source review; independent clinical review pending.
Downregulation versus desensitization
Desensitization is a broader description of a weaker response. Receptors can become less responsive without a lasting reduction in their number, while internalized receptors may be recycled or degraded. Downregulation should therefore not be used as a synonym for every loss of effect.
References: [1]
How researchers distinguish them
Imagine that repeated exposure produces a smaller response. To claim receptor downregulation, investigators need evidence about receptor abundance or availability, not only the response itself. Changes downstream of the receptor or in drug exposure could also explain the observation.
What cannot be inferred
A cellular adaptation experiment does not identify a universal break length for users of unrelated compounds. Recovery can depend on the receptor, exposure and model. Reports that an intervention stopped feeling effective do not establish which mechanism caused the change.