What is the target organ of epinephrine and norepinephrine?

Epinephrine and norepinephrine, also known as adrenaline and noradrenaline, are not specific to a single target organ. Instead, they act on a wide range of organs and tissues throughout the body, playing a key role in the sympathetic nervous system's "fight-or-flight" response.

Here are some of the major target organs and their responses to epinephrine and norepinephrine:

* Heart: Increased heart rate and contractility (pumping force).

* Blood Vessels: Constriction of blood vessels in the skin, digestive system, and kidneys; dilation of blood vessels in skeletal muscle.

* Lungs: Relaxation of smooth muscle in the bronchioles, leading to bronchodilation (widening of airways).

* Liver: Stimulation of glycogenolysis (breakdown of glycogen into glucose), leading to increased blood sugar levels.

* Skeletal Muscle: Increased glucose uptake and glycogenolysis.

* Brain: Increased alertness, focus, and cognitive function.

* Sweat Glands: Increased sweating.

* Digestive System: Reduced digestive activity, including slowed motility and reduced secretions.

It's important to note that the specific effects of epinephrine and norepinephrine can vary depending on the:

* Target organ: Different organs have different receptors for these hormones, leading to varying responses.

* Concentration of hormones: Higher concentrations can lead to more pronounced effects.

* Other hormones and neurotransmitters: The effects of epinephrine and norepinephrine can be modified by other hormones and neurotransmitters present in the body.

Overall, epinephrine and norepinephrine act as powerful regulators of the body's stress response, preparing it for immediate action and enhancing survival in emergency situations.