Diseases of the nervous system Flashcards
basics on Spina Bifida
a neuronal tube defect. occurring when vertebrae don’t form properly around the spinal cord leaving a ‘gap’ in the spinal cord
severity of spina bifida depends on
where the ‘gap’ is located
spina bifida causes problems with
movement, bladder and bowel
spina bifida is associated with
Hydrocephalus- excess fluid in the brain
the higher up the spine where the gap has occured
the more neuronal function the patient will have
when does the spine fail to close propely
during the first month of pregnancy
function fo CSF
produces a constant, controlled environment for the brain cells and protects from toxins. Prevents escape of NT
what may cause the BBB to become more permeable allowing substances normally excluded from he blood brain barrier
inflammation irradiation and tumours
which solutes have the same inc ocnentration in the CSF as the blood
CSF=blood
Na+
Cl-
HCO3-
Osmolarity
[CSF}< blood
K+ Cas2+ Glucose Amino acids pH cholesterol protein
solutes CSF> blood
Mg2+
Creatinine
which substances are usually negligible in CSF
cholesterol and protein
urinary incontinence
a condition when a individual suffer from involuntaryy leakage of urnine
causes of urinary incontinence
1`- ads release reduction
- diuretcis which inhibit Na+ reabsorption
- anticholinergics- inhibit muscuarinic ACh receptors- less detrusor muscle contraction
- dpamine antagonist- less NT available so less detgusor regulation
antimuscarinics help urinary inconitence by
cholinergic antagonists block activate of muscarinic ACh receptors therefore inhibiting detrusor muscle contraction and keeping internal sphincter closed - treats urge to wee
what is used to treat overflow UI
cholinergic antagonist- increases detrusor muscle contraction
what would be targeted for an antagonist drug for urinary incontinence
muscarinic ACh receptor
what would be prescribed to someone who constantly needs to wee?
drug which binds to muscarinic receptor to inhibit contract or detrusor
stroke basics
occurs when the blood supply to part of the brain are cut off. Blood carrying oxygen and nutrients can no longer reach certain cells, so they can n longer aerobically respire
two types of stroke
ischaemic- block (80%)
Haemorrahgic - bleed (20%)
deficits will depend on
how large the are of the brain being supplied is, s well as how long the occlusions have occurred
death of neurones during stroke is due to
excitotoxicity
excitotoxicity
- Lack of oxygen and sugar means ATP cannot be generated
- ATP reliant transporters like Na+/Ca2+ fail
- Depolarization too much calcium flows in
- Calcium triggers release of Glutamate (NT) into synaptic cleft
- NMDA receptor stimulated by Glu, when certain level of depolarization calcium block in AMPA channel allows the post synaptic neurone to be depolarized further
- Over excitation
- Calcium causes and increase in:
- ->Free radicals and
- ->ROS
- ->Calpain
- -> Endonucleases
- ->ATPases
- -> Phospholipases
- Membrane becomes more permeable harmful chemicals get into cell
- Mitochondria break down- releasing apoptotic factors
- Necrosis- releases more Glu
- VICIOUS CYCLE.
what may also occur after stroke
reperfusion injury
reperfusion injury
the tissue damaged caused when the blood supply return to the tissue after a period of schema or hypo
why does reperfusion cause damage to tissue
The absence of oxygen and nutrients from the blood during the ischemic period creates a condition in which the restoration of circulation results in inflammation and oxidative damage- oxidative stress-
when blood flow is restored and oxygen reintorduced
there are not enough antioxidants (not produced during hypoxia)= oxidative stress
- oxygen free radicals destroy cell membrane and leads to necrosis
which TF react to hypoxia
HIF -mediates the effects of hypoxia- e.g. helping the cells adapt to low oxygen conditions - growth of blood vessels
stroke and the brainstem
- can affect both sides of the body nd leave someone in ‘locked in’ state- unable to speak or achieve any movement below the neck
- usually causes death since the damage can prevent vital functions e.g. breathing
medulla
breathing, swallowing, bp, hr, vomiting, sneezing, coughing
midbrain
vision adhering, digestion, hr, br
pons
breathing and regulation of deep sleep
which is the arty most often occluded in stroke
Middle cereal artery- which supplies frontal lobe and lateral surge of the temporal and parietal lob
cerebellum and stroke
may result in lack of coordination, clumsiness, shaking or the muscular difficulties
if a stroke occurs in the right side of the brain
the right side of the body will be affected
- paralysis of the left side of the body
- vision problems
- memory loss
- quick, inquisitive behavioural style
stroke on the left side of the brain
- affects right side of the body
- paralysis
- speech and language problems
- slow, cautious behavioural style
- memory loss
parietal
unable to understand spoken or written language
temporal
decreased visual and verbal memory and decreased understanding of words
occipital
disability involving vision
frontal lobe
- personality change
- changing emotions
- decreased voluntary movement
- hard to convert thoughts into words
biomarkers of stroke
correct diagnosis of ischaemic stroke is essential to treat and prevent further stroke.
-BNP
CRP
-lipoptein associated phosplipase A2
what is the treatment for sichaemic stroke
T-PA
T-PA
tissue-plasminogen actiavtor
- dissolves blood clot by bidding to plasminogen and activating plasmin which dissolves fibrin
what synthesises CSF
ependymal cells in the choroid plexuses of the ventricles of the brain
