Introduction to the ANS

Question 1

What substance is released in each nervous system?

Answer 1

Parasympathetic : Ach throughout (long pre, short post)

Sympathetic: Ach at pre (short) , NA at post (long) / Ach to adrenal medulla -> A or NA to effector / rare cases of ACH throughout e.g sweat gland

Question 2

What are the two types of receptors?

Answer 2

Nicotinic : ion channel (fast) , found at all autonomic ganglia, stimulated by nicotine/ Ach

Muscarinic : G- protein coupled (slower), found at all effector organs innervated by post ganglionic parasymp. fibres, stimukated by muscarine/Ach

Question 3

Where are the sub types of muscarinic receptors found?

Answer 3

M1 : nerual

M2: cardial

M3: exocrine and smooth muscle

M4: periphery (prejunctional nerve endings (inhibitory))

M5: striatal dopamine release

*all 5 can be found in the brain

Question 4

What are the different types of adrenal receptors? Where are they found?

Answer 4

alpha 1, alpha 2, beta 1, beta 2

found in sympathetic NS