Hi, this is Tom from 0.0.5. In this video, I'm going to be going through adrenaline,

and you can find written notes on this topic at 0.0.5.com slash adrenaline, or in the 0 to finals

endocrine system book. And you can find flashcards and questions to train your knowledge

and help you remember the information for longer at members.0 tofinals.com.

So let's jump straight in.

Adrenaline, also known as epinephrine, is a catecholamine hormone responsible for the fight or flight response to danger.

It is produced by the chromaffin cells in the medulla or the middle part of the adrenal glands.

Adrenaline helps the body to respond to a potential threat. It has a short duration of

action helping with an intense burst of physical activity, for example fighting or running away

from danger, after which the effects disappear. Noradrenaline, which is also known as nor epinephrine, is a closely

related catecholamine that mainly functions as a neurotransmitter throughout the central nervous system

and the peripheral nervous system. Neurotransmitters are used at synapses to deliver a nerve signal from one cell to the next.

This might be from one neuron onto the next neuron or from a neuron to another type of cell at what is

called the neuro effector junction, for example, from a neuron

to a muscle cell.

Noradrenaline is also produced by the adrenal medulla and released into the general circulation

as a hormone, but in smaller amounts and with a smaller role than adrenaline.

Let's talk about adrenaline release.

Adrenaline is released in response to a potential threat.

Various sensory inputs, for example, sight, sound, smell and touch,

collect information about a potential threat.

These inputs are processed in their relevant brain areas, for example the visual cortex for sight.

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