Epinephrine

Definition

Epinephrine, also known as adrenaline, is a hormone and neurotransmitter produced by the adrenal medulla. It plays a crucial role in the body's fight-or-flight response by increasing heart rate, blood flow to muscles, and blood sugar levels.

5 Must Know Facts For Your Next Test

1. Epinephrine is released from the adrenal medulla in response to stress or danger.
2. It binds to adrenergic receptors on target cells, triggering physiological changes such as increased heart rate and energy mobilization.
3. Epinephrine stimulates glycogenolysis in the liver, leading to an increase in blood glucose levels.
4. It causes bronchodilation, which helps improve airflow in the lungs during stress or allergic reactions.
5. Synthetic epinephrine is used medically to treat conditions like anaphylaxis, cardiac arrest, and asthma attacks.

Review Questions

• What gland releases epinephrine and under what circumstances?
• How does epinephrine affect blood glucose levels?
• Name two medical conditions for which synthetic epinephrine can be used as a treatment.

Related terms

Adrenal Medulla: The inner part of the adrenal gland that produces epinephrine and norepinephrine.

Adrenergic Receptors: Receptors on target cells that bind to epinephrine and norepinephrine, mediating their physiological effects.

Glycogenolysis: The biochemical process of breaking down glycogen into glucose, stimulated by hormones like epinephrine.