Noradrenaline And Adrenergic Receptors

Question 0

Adrenaline

Answer 0

• chemically related to noradrenaline
• both belong to the catecholamine
• released by adrenal gland as hormone
• stimulates same receptors within the SNS as NA, have same effect

Question 1

What is noradrenaline made of?

Answer 1

-formed from tyrosine (non-essential amino acid) , which is obtained from food or synthesized from phenylalanine.

Question 2

What are the receptors responsive to Noradrenaline and Adrenaline?

Answer 2

Adrenergic receptors

• α receptors
• β receptors

Question 3

What are the type of adrenergic receptors

Answer 3

G-coupled protein receptor

Question 5

α receptors subtypes

Answer 5

α1 receptors

α2 receptors

Question 6

β receptors subtypes

Answer 6

β1 receptors
β2 receptors
β3 receptors

Question 7

α2 receptors

Answer 7

• inhibitory (Gi)
• causes contraction of the blood vessels
• also located presynaptically and act as negative feedback regulator of neuronal firing, inhibiting noradrenaline release from terminal (Gi)

Question 8

β1 receptors

Answer 8

• stimulatory (Gs)
• found in the heart, have an excitatory effect
• although in gut, activation leads to relaxation

Question 9

β2 receptors

Answer 9

• stimulatory (Gs)
• expressed in smooth muscle and some blood vessel, leads to vasodilation
• in bronchial smooth muscle, leads to bronchodilation

Question 10

β3 receptors

Answer 10

• stimulatory (Gs)

- present in fatty adipose tissue and some smooth muscle (intestine, gall bladder and urinary bladder)

Question 11

α1 receptors

Answer 11

• linked to excitatory G-proteins (Gq)

- found in much of the smooth muscle