Histology of Nerve (use notes and tophat) Flashcards
Structures of PNS vs CNS
CNS - brain, optic nerve, spinal cord, BS, cerebellum
PNS - nerves, ganglia, neurons outside CNS
Somatic sensation
touch, pain, vibration, proprioception
Enteric nervous system vs visceral nervous system
enteric regulates the movement of water and electrolytes in the gut, whereas the visceral nervous system is stretch, nausea, and temperature of stomach. Both are involuntary
Which type of axon is unmyelinated?
C type
What are some demyelinating diseases?
multiple sclerosis, guillen barre, charcot marie tooth, PML
What are the neuron morphologies and their functions?
Bipolar: special senses, Multipolar: motor and interneurons, Pseudounipolar: sensory neurons in ganglia
Functions of CNS glia: astrocytes, oligodendrocytes, ependymal cells, and microglia.
Astrocytes = fibrous, maintain BBB, move metabolites, and modulate neuronal activity
Microglia = phagocytes of CNS
Oligodendrocytes = make CNS myelin
Ependymal cells = epithelial lining of ventricles that have choroid and cilia that produce CSF
Where’s flow CSF?
4th ventricle> subarachnoid space> canal of spinal cord
What’s function and structure of BBB?
filters and maintains water/ions of CNS. Made of a bunch of tight junctions and pericytes. Diseases involved: meningitis, HIV encephalitis, rabies, Alzheimer’s
Glial cells of the PNS
Schwann cell which makes myelin and satellite which does metabolic exchange
What are the cholinergic and adrenergic receptors?
Cholinergic: nicotinic and muscarinic
Adrenergic: alpha = NE, EP
beta = EP, NE
What are the two neurons and ganglionic of sympathetic nervous system?
1st neuron comes from IML of T1-L2, 2nd neuron is ganglia. Pre ganglionic fibers = white, post are gray
What are PNS neurons/ fibers?
1st neurons are cranial and sacral (S2-S4). 2nd neuron is ganglia near effector organ. Pre synaptic fibers are sacral such as splanchnic
This NT is in all autonomic preganglionic neurons, parasympathetic postganglionic neurons, and NMJ
Acetylcholine
This NT is a monoamine, most sympathetic postganglionic except sweat glands and renal artery
Norepinephrine
This NT binds to adrenal medulla chromaffin cells
Epinephrine
Where are nicotinic receptors found?
Where are muscarinic receptors found?
target organs receiving parasympathetic innervation
Where can you find the alpha and beta adrenergic receptors?
a1 - vascualr smooth muscle/sphincters
a2 - nerve endings
B1 - heart
B2 - vascular/ non vascular smooth muscle
What causes NMJ transmission disorders?
Interruption of presynaptic release of acetylcholine, blocking of post synaptic receptors, or too much acetylcholine
What are the two divisions of the nervous system (not PNS and CNS)?
Sensory Division - can be somatic which is perceived consciously or visceral which is not perceived consciously
Motor Division - can be somatic which is voluntary and autonomic which is involuntary motor (parasympathetic- near organ or sympathetic- close to CNS)
What are some symptoms of multiple sclerosis?
fatigue, vision problems, numbness, muscle spasms, pain, depression
What are symptoms of diabetic neuropathy?
numbness, sharp pain, reduced ability to feel temp, increased sensitivity
What is multiple sclerosis?
Autoimmune disorder that causes inflammation and demyelination of CNS due to damaged oligodendrocytes
What is diabetic neuropathy?
High blood glucose injures nerves, impaired axon growth leading to usually pain and numbness in legs and feet. Due to Schwann cell dysfunction
