Autonomic nervous system Flashcards
What is the autonomic nervous system
part of the peripheral nervous system involved with involuntary motor control of smooth muscle and glands
Sympathetic ANS: “fight or flight” response
Parasympathetic ANS: “rest and digest” response
Where does the sympathetic nervous system arise from
the thoracic and lumbar regions
where does the parasympathetic nervous system arise from
the cranial nerves (brainstem) and the sacral region (pelvic splanchnic nerves- S2-S4 )
How are the sphlanchnic nerves involved with the autonomic nervous system
greater splanchnic - T5-T9 –> coeliac plexus –> sympatehtic innervation of the foregut
lesser splanchnic T10-T11 –> superior mesenteric plexus –> sympathetic innervation of the midgut
least splanchnic T12 –> inferior mesenteric plexus –> sympathetic innervation of the hindgut
pelvic splanchnic nerve –> parasympathetic innervation of bladder, genetailia, rectum
eyes sympatehtic vs parasympathetic
sym- pupil dilation and production of aquous humor
para - pupil constriction
what does the adrenal medulla do
secrete adrenaline and noradrenaline in response to sympathetic stimulation from the greater sphlancnic nerve
bladder symp vs para
symp - relaxation of destrusor and constriction of urinary sphincter (retention of urine)
para - constriction of detrusor muscle and relaxation of urianry sphincter (release of urine)
symp vs para sexual fucntion
para - arousal / erection
symp - orgasm and ejaculation
symp vs para lungs
symp - bronchodialtion
para - bronchoconstriction
route parasympathetic to target organ
CNS –> long lightly myleinated axon –> AcH bind to nicotinic receptors –> AcH released to stimualte muscarinic receptors on target organ
receptors and neurotrasmitters parasympatehtic nervous system
nicotinic and muscarinic receptors
acetylcholine
route most sympatehtic nerve to target organ
CNS–> short lightly myelinated axon –> AcH onto nicotinic receptors on sympathteic chian ganglion –> long axon to release noradrenaline onto alpha and beta receptrs on target organ
route sympatehtic to adrenal medulla
CNS –> lightly myelinated axon –> AcH onto nicotinic receptors on adrenal medulla –> release of noradrenaline and adrenaline into sympathetic circulation
route sympathetic to sweat glands
CNS –> AcH onto nicotinic receptors on sympatehtic chain ganglion –> long axon –> AcH onto muscarinic receptors on sweat glands
what are anticholinergic drugs
Antimuscarinic agents operate on the muscarinic acetylcholine receptors. The majority of anticholinergic drugs are antimuscarinics.
