Intro to Autonomic Physiology

Question 1

direction of efferent and afferent signals

Answer 1

Afferent: sensory signals towards the CNS
Efferent: effector signals away from the CNS

Question 2

sympathetic and parasympathetic nervous system functions and origins

Answer 2

sym: stress responses and energy consumption functions, thoracic-lumbar origin
para: restorative and energy saving functions, cranial-sacral origin

Question 3

primary function of the ANS

Answer 3

maintaining homeostasis

Question 4

where do pre ganglionic fibres arise and terminate

Answer 4

arise in CNS
terminate at ganglia (a site where two or more cells synapse)

Question 5

where do post ganglionic fibres arise and terminate

Answer 5

arise at ganglia
terminate on effector cells

Question 6

anatomy of sympathetic NS

Answer 6

short pre ganglionic fibres, ganglia are close to the CNS
most are prevertebral and run down the length of the spine
paravertebral are in the digestive tract

Question 7

anatomy of parasympathetic NS

Answer 7

long pre ganglionic fibres, ganglia next to effector cells
short post ganglionic fibres

Question 8

what neurotransmitter and receptor are present at ganglia

Answer 8

acetylcholine
nictinic AChRs

Question 9

what neurotransmitters and receptors are present at the end of post ganglionic neurons

Answer 9

acetylcholine
muscarinic AChRs
sympathetic NS only: noradrenaline, adrenoreceptors

Question 10

what is NANC transmission and what are the transmitters it uses

Answer 10

non-adrenergic, non-cholinergic transmission
sym: ATP (rapid), neuropeptide Y (slow)
para: nitric oxide (intermediate), vasoactive intestinal peptide (slow)