Neurophysiology Flashcards
Located in or near the effector organs
Parasympathetic Ganglia
Located in the paravertebral ganglia
Sympathetic Ganglia
Preganglionic neurons of sympathetic nervous system
T1-L3 spinal cord, thoracolumbar region
Preganglionic neurons of parasympathetic nervous system
originate in nuclei of cranial nerves and in spinal cord segments S2-4 or craniosacral region
Chromaffin cells
80% epinephrine
20% norepinephrine
short preganglionic nerve axon
sympathetic
long preganglionic nerve axon
parasympathetic
long postganglionic nerve axon
sympathetic
short postganglionic nerve axon
parasympathetic
NT for sympathetics ub effector organs
NE, except in sweat glands, it is ACh
Alpha-1 (Gen overview)
sympathetic, smooth muscle, Gq, increases IP3/Ca
Alpha-2 (Gen overview)
sympathetic, GI tract, Gi, decreases cAMP
Beta-1 (Gen overview)
sympathetic, heart, Gs, increases cAMP
Beta-2 (Gen overview)
Sympathetic, smooth muscle (lungs), Gs, increases cAMP
Nm (N1) (Gen overview)
Cholinergic, skeletal muscle, opens Na/K channels
Nn (N2) (Gen overview)
Cholinergic, autonomic ganglia, opens Na/K channels
M1 (Gen overview)
Cholinergic, CNS, Gq, increased IP3/Ca
M2 (Gen overview)
Cholinergic, Heart, Gi, decreases cAMP
inhibitory to heart
M3 (Gen overview)
Cholinergic, Glands & Sm Muscle, Gq, increase IP3/Ca
excitatory in sm muscle and glands
Radial muscle of Iris
alpha-1 receptor
equally sensitive to epinephrine and NE but only NE is released from these neurons
platelets and fat cells
Alpha-2 receptor, produce inhibition
bronchial smooth muscle
Beta-2 receptors, cause relaxation, more sensitive to epinephrine
Relaxation of Bladder Wall
Beta-2 Receptors
In autonomic ganglia of sympathetic and parasympathetic NS
N2 receptor (Nn) also found in adrenal medulla
Receptor in NMJ
N1 (Nm)
alpha-1 agonist
NE, phenylephrine
alpha-1 antagonist
Phenoxybenzamine, Phentolamine, Prazosin
alpha-2 agonist
clonidine
alpha-2 antagonist
Yohimbe
Beta-1 Agonst
NE, Isoproterenol, Dobutamine
Beta-1 Antagonist
Propranolol, Metoprolol
Beta-2 agonist
isoproterenol and albuterol
Beta-2 antagonist
propranolol and butuxamine
Nicotinic Agonist
ACh, Nicotine, Carbachol
Nictonic Antagonist
Curare and Hexamethonium (ganglion not NMJ)
Muscarinic Agonist
ACh, Muscarine, Carbachol
Muscarinic Antagonist
Atropine
Receptor to increase HR, contractility, and AV node conduction
Beta-1 (sympathetic)
Receptor that contricts BV in skin and splanchnic
alpha-1 (sympathetic)
receptor that dilates BV in skeletal muscles
Beta-2 (sympathetic)
Receptor that decreases GI motility
alpha-2, beta-2 (sympathetic)
receptor that contricts sphincters in GI tract
alpha-1 (sympathetic)
receptor that dilates bronchiolar smooth muscle
beta-2 (sympathetic)
ejaculation receptor
alpha (sympathetic)
Receptor that relaxes bladder wall
beta-2 (sympathetic)
Receptor that constricts bladder sphincter
alpha-1 (sympathetic)
Receptor that increases sweating
M (sympathetic cholinergic)
Receptor that increases renin secretion
beta-1 (sympathetic)
Receptor that increases lipolysis
beta-1 (sympathetic)
Receptor that decreases HR, Contractility and AV node conduction
M2 (parasympathetic)
Receptor that increases GI motility and relaxes GI sphincters
M3 (parasympathetic)
Receptor that constricts bronchiolar smooth muscle
M3 (parasympathetic)
erection receptor
M (parasympathetic)
Receptor that contracts bladder wall
M3
Receptor that relaxes bladder sphincter
M3
Autonomic centers in the medulla
vasomotor, respiratory, swallowing, coughing and vomiting centers
Autonomic centers in the pons
pneumotaxic center
Autonomic centers in the midbrain
micturition
Autonomic centers in the hypothalamus
temperature regulation center, thirst and food intake
mechanoreceptors
pacinian corpuscles, joint receptors, stretch receptors in muscle, hair cells in auditory and vestibular systems, baroreceptors in carotid sinus
Photoreceptors
rods and cones of the retina
Chemoreceptors
Olfactory, taste, osmoreceptors, carotid body with O2 receptors
Nociceptors
extreme pain and temperature
A fiber - Ia
muscle spindle afferents, largest diameter, fastest, motor neuron
A fiber - Ib
golgi tendon organs, largest diameter and fastest
A fiber - II
touch and pressure, secondary afferent of muscle spindles, medium diameter and medium velocity
intrafusal fibers
gamma-MN, medium diameter and medium velocity
III (A-delta)
touch, pressure, fast pain, and temperature - small diameter, medium conduction velocity
B fibers
Preganglionic autonomic fibers, small diameter and medium conduction velocity
C fibers- IV
Slow pain; postganglionic autonomic fibers, smallest diameter and slowest conduction velocity
Onion like structures in the subcutaneous skin surrounding unmyelinated nerve endings
Pacinian Corpuscle, vibration and tapping, rapidly adapting
Receptor present in nonhairy skin
Meissner’s corpuscle, senses velocity, rapidly adapting
Encapsulated mechanoreceptor that senses pressure
Ruffini’s corpuscle, slowly adapting