Neuro Flashcards
Ach receptors
Muscarinic in post ganglionic para and symp for sweat only
Smooth muscle,glands and brain,
GPCR, blocked by atropine
Nicotinic for pre ganglionic both
In NMJ, autonomic ganglia and CNS
Ligand gated sodium ion channels
(Post ganglionic symp is Noradr)
ACh termination from synaptic cleft
- Diffusion
- Catabolism by pseudocholinesterase
- Acetylcholinesterase in post synaptic membrane
- Reuptake of choline into presynaptic terminal
Noradrenergic nerves stimulation and termination
In granulated vesicles in nerve
Released by exocytosis
Acts on postsynaptic
Terminated by:
Reuptake to pre synaptic and by MAO
Catabolised by COMT in synaptic cleft
Stretch reflex
Stretch
Muscle spindle activated
1a fibre to dorsal
Alpha motor neuron glutamate
Ventral back to effector
Inhibition antagonistic muscle
Monosynaptic
Dorsal column
Fine touch, vibration ans proprioception
Ipsiliateral until medulla
Synapse at cuneate and gracilis nuclei in medulla
Ascend medial leminiscus until thalamus (ventral posterior lateral nucleus) synapse again
Ventral STT
Pain and temp
Crosses at level in spinal cord
Synapses there in stt
Up to thalamus ventro posterior lateral nucleus and synapses
UMN vs LMN
UMN - initially flacid then spasicity, clonus, plantars up (CST)
LMN - fasciculations, hypotonia, no reflexes
Visual near response
Accomodation
Visual axis convergence
Pupillary construction
Light enters eye
Through cornea to retina
Rods and cones
Bipolar cells
Optic nerve
Chiasm
Optic tract
LGN
Decerebrate vs decorticate
Decerebrate - extension, due to unnoposed reticulospinal extension, from mid collicular trnasection (below red nucleus), cause eg uncal herniation
Decorticate - arms flexed from rubrospinal and legs extended, from lesion above red nucleus, can become decerebrate, on hemiplegic side after haemorrhage or thrombosis internal capsule
Components basal ganglia
Striatum
Putamen
Globus palidus
Substantia nigra
Caudate nucleus
Subthalamic nucleus
Nucleus accumbens
Parasynpathetic cranial nerves
3,7,9,10
3 - from 2, to edibger westphal nucleus (midbrain), to ciliary ganglia (construction)
7 - splenopalatine ganglion -> lacrimal gland nasal glands
Submandib ganglion to submandib and subling gland s
9- otic ganglion to parotid causing saliva
Fuel for cardiomyocytes
Fatty acids when resting
Where is calcium in smooth muscle
Extra cellular (rather than sr in skeletal)
Smooth muscle contraction
Ach to muscarinic
Calcium influx
Activation calmodulin dependant light chain kinase
Phosphorykation myosin (no troponin)
Increased myosin ATPase activity
Binding myosin to actin
Contraction
Neurotransmitters and smooth muscle activation
ACh - contraction (decreses potential and increases spike frequency)
Noradrenaline - relaxation (increased potential, decreases spike)
20% of myosin and 100% less atp in smooth than skeletal but similar force, slower contraction
Stretch causes contraction in abscence innervation
Muscarinic and nicotinic receptors
M - GPCR slow, smooth muscle and glands e.g. sweat iris and parasynpathetic smooth muscle
N - ligand gated and pre synaptic both and to adrenal plus somatic to skeletal muscle
Dorsal column
Fine touch, vibration, proprioception
Medulla
Synapse in gracillus and cuneate nuclei
Cross midline in medulla
Ascend medial lemniscus
Vpl nucleus thalamus
To cerebral and somatosensoet nuclei
Ventrolateral spinothalamic tract
Pain and temp
A delta and c
Glutamate and substance p
Crosses at level or 1/2 up
VPL nucleus and synapses
Ear bones
M - tm tensoe tympani oulls mediallh
I
S - attached oval window stapedius pulls foot plate of stapes out of oval window
Hair cells
In cochlea for hearing and semicirc for balance
Organ of corti - hearing
Urticle - horizontal acceleration
Saccule verticle acceleration
High k in endolymph, resting potential -60
Tympanic reflex
Tensor tympani and stapedius contract
Inhibits strong sound conduction
Central auditory pathway
Viii to dorsal and vent cochlear nuclei in bs
To inferior colliculus in midbrain
To thalamus and auditory cortex tenporal lobe
Hearing loss
Conductive e.g. wax
Rinnie bone greater than air
Weber to affected side
Sensoruneural e.g. hair call dysfunction / aminoglycosides
Rinnie air greatee than bone
Weber to other side (unnafected)
