Nervous system divided into
CNS PNS
Preganglionic nerve originates in the
CNS, usually myelinated
Post-ganglionic nerve is
nonmyelinated and terminates in smooth or cardiac muscle, exocrine glands
In between pre-ganglionic and post-ganglionic is
ganglion
Ganglion
receptor between nerves
Neuroeffector transmitter
effector organ
Parasympathetic cranial innervation
III, VII, IX, X
Parasympathetic pre-ganglia are
long
Sympathetic pre-ganglia are
short
Parasympathetic connects the brain to the sacrum
craniosacral
Sympathetic originates in the spine
Thoracolumbar
Acetylcholine
All preganglionic fibers
Post-ganglionic fibers
parasympathetic
post-ganglionic fibers innervating sweat
glands
Somatic system
Norepinephrine
post-ganglionic fibers- sympathetic
Cholinergic receptor families
muscarinic
nicotinic
nicotinic
Nm
Nn
Ligand gated ion channels (na+, ca2+)
NM =
muscle
Nn = neuron
Ionotropic receptors
muscarinic
5 subtypes M1-M5
G-protein coupled receptors
M1&M3- IP3
and DAG as second messengers
M2- Adenyl cyclase
Dont learn the Ms
for muscarinics, too far
Key Nm & Nn
Nm - neuromuscular junction
Nn - autonimic ganglia, adrenal medulla
Key Muscarinic
do not memorize M1-5
Key parasympathetic
affector, vs transmission vs neuromuscular junction
****A2
sketchy mechanisms, learn em
a2 stops release of
norepi
a2 is kind of a weird norepi ____
negative feedback loop/release valve
b1, b2, b3
b1 have equal affinity for epi and norepi
b2 have a higher
affinity for norepi
located on post-synaptic effector cells
adenyl cyclase and cAMP are the second messengers for
b1,b2,b3
norepinephrine are
presynaptic neurotransmitter
synthesis of norepi fromm
dopamine
norepi released into
synapse
a2 is found in the
presynapse
cOMT
catechol-o-methyltransferase
neurotransmitter can be put back into
pre-synapse
MAO
monoamineoxidase
norepi can be
degraded in two places or recycled
when norepi is released, one of 4 things can happen
binding
degredation x2 enzymes
reuptake