Epinephrine + Fight/Flight

A. Epinephrine Overview

What hormone triggers the fight-or-flight response?

Epinephrine (also called adrenaline)

Where is epinephrine produced?

The adrenal glands

Is epinephrine water-soluble or nonpolar?

Water-soluble and polar

Why can’t epinephrine diffuse into the cytoplasm?

It has hydroxyl and amino groups and is polar

How does epinephrine affect tissues selectively?

Only tissues with epinephrine receptors can respond

B. Physiological Effects

Why does epinephrine decrease digestion?

Digesting is not necessary during an immediate threat

Why does epinephrine increase heart rate?

To deliver more food and oxygen to cells

Why does epinephrine cause pupil dilation?

To allow more light into the eyes for better sensory input

Why does epinephrine cause bronchiole dilation?

To increase oxygen intake for cellular respiration

How does epinephrine increase available energy?

By converting glycogen to glucose

C. Effects on Liver Cells

What specific effect does epinephrine have on liver cells?

It induces the hydrolysis of glycogen into glucose

What happens to the glucose produced in the liver?

It diffuses into the bloodstream to supply energy for fight or flight