What is receptor down-regulation?

What is receptor down-regulation?

Downregulation: An decrease in the number of receptors on the surface of target cells, making the cells less sensitive to a hormone or another agent. For example, insulin receptors may be downregulated in type 2 diabetes. CONTINUE SCROLLING OR CLICK HERE.

What is the difference between desensitization and tolerance?

Desensitization refers to the common situation where the biological response to a drug diminishes when it is given continuously or repeatedly. The term tolerance is conventionally used to describe a more gradual loss of response to a drug that occurs over days or weeks.

What causes receptor down regulation?

Receptor downregulation is characterized by a decrease in total receptor number in the cell due to endocytosis and subsequent degradation of the receptors caused by long-term exposure to agonists (see Fig. 5-7). Downregulation is also an important cellular mechanism during long-term administration of therapeutic drugs.

What is heterologous regulation?

Activation of one receptor could trigger processes that regulate the same or a different receptor (homologous or heterologous regulation, respectively) (1). Thus, control over the capacity of a GPCR to interact with β-ARRs could have major effects on signaling and trafficking of many receptors.

What causes receptor down-regulation?

Elevated levels of the hormone insulin in the blood trigger downregulation of the associated receptors. The internalization of the insulin molecules provides a pathway for degradation of the hormone as well as for regulation of the number of sites that are available for binding on the cell surface.

Why does receptor desensitization happen?

Homologous desensitization occurs when a receptor decreases its response to an agonist at high concentration. It is a process through which, after prolonged agonist exposure, the receptor is uncoupled from its signaling cascade and thus the cellular effect of receptor activation is attenuated.

Which of the following is an example of down regulation quizlet?

What is an example of down regulation? People with type 2 diabetes have high blood glucose, high insulin, but target tissues are so used to seeing that insulin that it no longer reacts to it or has the same effect, therefore producing less receptors.

What is down regulation quizlet?

Down-regulation. prolonged exposure to high hormone concentrations can decrease the # of receptors of that hormone; desensitizes the target cells, so they response less vigoursly to hormonal stimulation, preventing them from overreacting to persistently high hormone levels.

What are two possible mechanisms of desensitization?

There are two types of desensitization: homologous desensitization, which is defined as the agonist-induced reduction in cellular response that occurs when the receptor is stimulated only by this particular agonist, and heterologous desensitization, which is defined as the reduction in response of a particular receptor …