Brain and Spinal Cord Flashcards
What are the 4 types of neuroglia in the CNS
- Astrocytes
- Ependymal cells
- Oligodendritic cells
- Microglia
What type of astrocytes are found in gray matter and describe it’s appearance?
Protoplasmic astrocytes- numerous short branching processes
What type of astrocytes are found in white matter and describe them
Fibrous astrocytes- long unbranched processes
What is the function of oligodendrites?
Forms and maintains myelin sheath around several CNS axons
Describe microglia and their function
Small cells with slender processes- functions as phagocytes
Describe the appearance of ependymal cells
Cuboidal to columnar cells that have cilia and microvilli
Where can ependymal cells be found?
Lining the ventricle off the brain and central spinal canal of spinal cord
Blood-cerebral spinal barrier
What is the function ependymal cells?
Produce, monitor and assist in circulation of cerebral spinal fluid
What are the types of neuralgia in the peripheral nervous system?
Schwann cells and satellite cells
What is the function of the Schwann cells?
Form and maintain myelin sheath around a single PNS axon and participate in axonal regeneration
What are satellite cells?
Flat cells surrounding athe PNS cell bodies
What is the purpose of satellite cells?
Provides structural support
What are 2 demyelination disorders?
Multiple Sclerosis
Guillain Barre Syndrome
What are the effects of the myelin sheath?
Electrically insulates the axon
Increases speed of nerve impulse
What is the most accurate test of multiple sclerosis?
MRI
Describe multiple sclerosis
Disorder of slow and progressive demyelination of neurons in the CNS due to autoimmune response.
What autoimmune response causes multiple sclerosis?
Antibodies are produced against the myelin sheath of neurons which disrupts the propagation of action potential along the neurons.
Who is multiple sclerosis most common for?
More common in Caucasians than Blacks and Asians
What are 5 symptoms of multiple sclerosis?
Blurred vision due to optic neuritis, spasticity, fatigue, hyperflexia, cerebelli deficits
How would prevention of exacerbation of multiple sclerosis be performed?
Steroids in acute phase and interferon/glatiramer
What are the symptoms of Giullain Barre Syndrome?
Ascending limb weakness from the feet and loss of deep tendon reflexes
What are used to investigate Gullain-Barre syndrome?
Electromyography and nerve conduction studies
What is the most common cause of acute paralysis in North America?
Guillain Barre Syndrome
Briefly describe Guillain Barre Syndrome
Demyelinating condition of peripheral nervous system.
What causes Gullain-Barre syndrome?
Circulating antibodies may affect myelin of peripheral nerves usually following infection by Campylobacter jejuni
Distinguish between a nerve and a tract
Nerve- bundle of axons located in the peripheral nervous system
Tract- bundle of axons in the Central nervous system
Distinguish between ganglia and nuclei
Ganglia- clusters of neuronal cell bodies located in the peripheral nervous system
Nuclei- clusters of neuronal cell bodies located in the central nervous system
Name 3 parts of the brain stem
Midbrain, pons and medulla oblangata
What are the risk factors in a cardiovascular accident(stroke)?
High blood pressure, high cholesterol, diabetes, smoking, alcohol, obesity
What is the most common brain disorder?
Cardiovascular attack(stroke)
This disease is the third leading cause of death in America, affecting 500,000 people the U.S.A. each year?
Cardiovascular attack(stroke)
What could be the causes of a stroke?
Could be ischemic or hemorrhagic e.g. thrumbos or ruptured cerebral aneurysm
What is the fourth leading cause of death in persons over age 65?
Alzheimer’s disease
Describe Alzheimer’s disease
Degenerative or senile disease characterized by loss of reasoning and ability to take care of self
Where are most of the cerebrospinal fluid produced?
Lateral ventricles
Describe hydrocephalus
The accumulation of excess cerebrospinal fluid with increased pressure in the brain
Describe the cause of hydrocephalus
Brain abnormalities like congenital anomalies (like inflammation, tumors and subarachnoid hemorrhage) can interfere CSF circulation in the ventricles and arachnoid granulation
Name the types of hydrocephalus
- Obstructive(non-communicating)
- Non-obstructive (communicating)
How can pressure be relieved from hydrocephalus?
Application of ventriculoperitoneal shunts
Give the signs and symptoms of hydrocephalus
Obvious superficial cranial veins, damage to soft tissues
Headache and other signs of raised intracranial pressure