CNS disorders Flashcards
what are the two main sources of blood into the circle of willis
- internal carotid
- vertebral artery
ACA- anterior cerebral artery
- branches from internal carotid
- had many superficial and deep branches and anastomosis
MCA - middle cerebral artery
- branches from internal carotid
- 4 main branches
PCA - posterior cerebral artery
- branch from the basilar artery near the pituitary stalk at the ponotmesencephalic junction
supplies
- occipital lobe,
- inferomedial temporal lobe,
- a large portion of the thalamus
- upper brain stem,
- midbrain,
- lateral geniculate body
- hippocampus
- parahyippocampal gryus
CNS cells:
- neurons
- macroglia:
- microglia
What are macroglia and describe
derived from nerve cell linage
- astrocytes: provide structure
- oligodendrocytes: myleinate
- Schwann: mylinate in PNS
- ependymal cells: help produce CSF
Microglia
- derived from monocyte cell lineage
- immune cell of brain
- 10% of CNS cells
- clean foreign bodies
- are times where microglia stay active and cause damage
Cellular dysfunction: neural cell death
- apoptosis: programmed but can cause damage if it outside normal range of occurring
- necrosis: unplanned usually caused by an external factor, cell membrane gets disrupted and the insides affect other cells when they leak out
Cellular dysfunction: excitotoxicity
- free radicals: can be dangerous or harmful
- released during exercise but that helps the body understand how to deal with them
What regulates the extracellular environment of the CNS
- blood brain barrier: tightly joined endothelial cells; block diffusion
- ependymal cells: line ventricles and spinal canal and regulate metabolism
- regulate the extracellular environment and protect the nervous system structures
Amino acid Neurotransmitters
- glutamate: excitation
- GABA & Glycine: inhibitory
Amines Neurotransmitters
- cholinergic = acetylcholine
- biogenic: catecholamines, serotonin
- neuopeptides Neurotransmitters
- enkephalins
- b-endorphins
- substance P
gaseous Neurotransmitters
- nitrous oxide NO
Sympathetic NS neurotransmitters and what they cause as well as receptor types
- adrenergic stimulate sympathetic NS
- can have a positive effect meaning it increases sympathetic response or a negative effect meaning that it decreases sympathetic response
- receptor types: alpha and beta
- nicotinic receptor at preganglioic neuron
parasympathetic Neurotransmitters
- cholinergics for both pre and post ganglionic
- only positive effects
- adrenergics
- cholinergincs
- stimulate sympathetic NS
- stimulate parasympatheic NS
beta blockers
vs
alpha blockers
- inhibit sympathetic (beta receptors mostly)
- inhibit sympathetic (alpha receptors mostly)
anticholinergics
inhibit parasympathetic NS
what are side effects of increase in parasympathetic function
- GI distress: nausea, vomiting, diarrhea,
- abdominal cramping,
- bronchoconstriction,
- increase salivation
- bradycardia
- pupils constricted
- impacts vision
Biogenic amines
- norepinephrine
- Dopamine
- serotonin
- work together to regulate attention and alertness
Norepinephrine effects with Mental health regulation
- attention
- motivation
- pleasure
- reward
- mood
Dopamine
- alertness
- energy
- Anxiety
- involved in movement quality
Serotonin
- obsession
- compulsions
CNS disorders
Infections
neoplasm
vascular
trauma
degenerative
Infectious disorders of the CNS
- Meningitis (viral, tuberculous, bacterial)
- encephalitis
- brain abscess
Neoplasms
- tumor
Vascular- CNS disorder
TIA
stroke
Trauma- CNS disorder
TBI
Degenerative disorders - CNS disorders
- get progressively worse
- ALS
- Alzheimer’s
- huntington disease
- MS
- Parkinson
Examples of the variety of clinical manifestations of CNS disorders
- Sensory disturbances
- Movement disorders
- disorders of coordination movement
- deficits of higher brain function
- altered states of consciousness
- emotional instability
- memory problems
- brainstem dysfunction
- autonomic system dysfunction
- aging and the CNS