The document discusses two catecholamine neurotransmitters, epinephrine and norepinephrine. Epinephrine, also known as adrenaline, is synthesized from phenylalanine and tyrosine and has a molecular weight of 183g. It is used to treat resuscitation, anaphylaxis, hypotension, shock, and asthma. Norepinephrine also acts as both a hormone and neurotransmitter and is involved in the stress response and fight-or-flight response by increasing heart rate, releasing glucose, and increasing blood flow to muscles. It has potent actions on both alpha-1 and beta-1 receptors.

1. Neurotransmitters –
Epinephrine and
Norepinephrine
Dr Zaid Azhar

2. Epinephrine
• Also known as Adrenaline
• Catecholamine,
• Derived from phenylalanine
and tyrosine
• Molecular weight – 183g

3. Synthesis

4. Adrenergic Receptors

5. Adrenergic Receptors

6. Adrenergic Receptors

7. Mechanism of Action

8. Mechanism of Action

9. Uses of Adrenaline
• Resuscitation
• Management of anaphylaxis
• Inotropic support in hypotension, shock, status
asthmaticus

10. Norepinepherine
Catecholamine with multiple
roles:
•Hormone
•Neurotransmitter

11. Synthesis

12. Functions
• Stress hormone
• Fight-or-flight response
• Increases heart rate
• Triggers the release of glucose
• Increases blood flow to skeletal muscle.
• Suppress neuro-inflammation

13. Actions
• Potent action-both a1 & b1 receptors
–Little action on b2
–Causes potent vasoconstriction (α)
–Lacks bronchodilating effect
–↑ systolic, diastolic & MAP
–Reflex bradycardia
–Metabolic acidosis

14. Comparison