Neurotransmitters

Question 1

What are neurotransmitters?

Answer 1

Neurotransmitters are endogenous chemicals that transmit signals across a chemical synapse to communicate information throughout the brain and body.

Question 2

What are the 3 major categories of NTs?

Answer 2

• Amino acids - glutamic acid, GABA, aspatic acid, glycine
• Peptides - vasopressin, somatostatin, neurontensin
• Monoamines - norepinephrine, dopamine, serotonin, acetylcholine

Question 3

What is the mode of action of NTs?

Answer 3

When electrically stimulated, NTs are released from synaptic vesicles in pre-synaptic neurones and released into the synaptic cleft. These neurotransmitters bond with receptors on the post-synaptic neuron.

Question 4

What are the types of receptors NTs bind to?

Answer 4

Depending on NT chemical property, bind different types of receptors.

• Ligand-gated ion channel
• GPCRs
• Kinase-linked receptors
• Nuclear receptors

Question 5

What are the types of NTs?

Answer 5

Neurotransmitters can be excitatory or inhibitory, depends on type of receptor it bonds to, therefore some can be both.

Question 6

How do excitatory NTs work?

Answer 6

By activating channels that allow the passage of positively charged ions in, usually Na+, or by inhibiting c. This create a voltage gradient across the cell membrane, allowing depolarisation, sending an electrical impulse through the nerve cell to repeat the process on the next neuron.

Question 7

How do inhibitory NTs work?

Answer 7

By inhibiting channels that allow the passage of positively charged ions in, usually Na+, or activating channels allowing negative charge in.