Neurology Part 2 Flashcards
Norepinephrine.
- An excitatory neurotransmitter (a.k.a Adrenaline)
- Increase Heart Rate
- In High amounts can cause; paranoia, anxiety, stress
- In Low amounts can cause; Depression and lethargy
Dopamine.
- An excitatory neurotransmitter
- Pleasure centre!
- ‘Reward centre of the brain’
- In High amounts can; anxiety and psychosis
- In Low amounts can; depression and lethargy
Serotonin.
- Inhibitory neurotransmitter
- Stabilizes our mood, feelings of well-being, and happiness
- ‘Happy hormone’
- High amounts can cause; Mood Swings
- Low amounts can cause; Anxiety and Insomnia
GABA (Gamma-aminobutyric acid).
- Inhibitory neurotransmitter
- Increases Cl- influx which promotes decreased cellular activity
- Reduces neuronal excitability by inhibiting nerve transmission
- High amounts can cause; Lethargy, Confusion, Sedation and Amnesia
- Low amounts can cause; Anxiety and Insomnia
Glutamate.
- Excitatory neurotransmitter
- Responsible for sending signals between nerve cells
- Plays an important role in learning and memory
- High amounts can cause; Anxiety
- Low amounts can cause; Low focus, Retention
Substance P.
- Excitatory neurotransmitter
- Pain sensation
Neurotransmission.
The transmission of nerve impulses between neurons
Process of Neurotransmission.
When a stimulus reaches the threshold stimulus it causes the axon membrane to depolarize, the rapid change in polarity across the membrane generates an action potential.
- Action Potential arrives at the axon terminal
- Voltage-gated Ca+ channels open
- Ca 2+ enters the presynaptic neuron
- Ca 2+ signals to neurotransmitter vesicles
- Vesicles move to the membrane and dock
- Neurotransmitters released via exocytosis
- Neurotransmitters bind to receptors
- Signal initiated in the postsynaptic cell
What occurs in the synaptic cleft during neurotransmission?
The neurotransmitters bind to their respective receptors after binding either an excitatory or inhibitory response will be delivered.
What occurs to the excess neurotransmitters?
The excess needs to be removed from within the cleft wither by enzymatic degradation or reuptake.
Enzymatic Degradation.
Enzymes such as; COMT, MAO and cholinesterase are released to degrade to excess waste.
Re-Uptake.
Neurotransmitter molecules that have been released at a synapse are reabsorbed by the presynaptic neuron that released them. Reuptake is performed by transporter proteins in the presynaptic membrane.
Which neurotransmitters are expelled through re-uptake?
- Dopamine
- Serotonin
- Norepinephrine
- Epinephrine
- Glutamate
Preganglionic Neurons.
Are a set of nerve fibres of the autonomic nervous system that connect the central nervous system to the ganglia.
Postganglionic Neurons.
Are a set of nerve fibres that are present in the autonomic nervous system which connects the ganglion to the effector organ.
Physical Dependence.
Physical dependence is a physical condition caused by chronic use of a tolerance-forming drug, in which abrupt or gradual drug withdrawal causes unpleasant physical symptoms.
*The body adapts to the presence of the exogenous substance and creates a tolerance *
Weening Protocol.
The protocol is initiated when a patient is ending treatment. Meaning that the substance is slowly decreased until the regular function is restored.
Psychological Dependence,
This occurs when the patient WANTS the drug and it is not related to the treatment of a diagnosis.
What are the Signs of Drug Abuse and Psychological Dependence
- Spending a great deal of time acquiring, using and recovering from the use of the substance
- Disruption of important activities because of substance use
- Using more than intended
- Compulsive use despite harm
- Tolerance – requiring more drugs over time
- Withdrawal symptoms if without drug
- Unsuccessful efforts to cut down
Define Headache.
Pain or discomfort in the head is caused b various factors. Described as; throbbing, pounding, painful etc.
headache is ONLY a symptom
How to treat a headache?
DO NOT treat without investigating, DO NOT treat of unsure. There are many underlying factors to a headache and they need to examine before administering treatment.
Migraine.
Chronic headache disorder. They last for more than 15 days per month for 3 months.
Pathology Sequealea for Migraine.
Trigeminal nerve irritation, inflammation within meningeal vasculature. (the headache is intense and within the meninges).
Two main Categorizations for Migraines.
- Without Aura- most common
2. With Aura- more pronounced visual disturbances precede the headache (symptoms occur before the migraine sets in)
Signs and Symptoms of Migraine.
- Prodrome fatigue
- Irritability (pre-migraine)
- Nausea and vomiting
- Intense headache
- Hypersensitivity to stimuli
- Sensory disturbances
Treatment of Migraines.
- Analgesiscs: NSAIDs, Tylenol
- Triptan (Serotonin agonists which induce calming sensations)
- Botox (Decreases the release of acetylcholine and acts as an anti-inflammatory)
- Caffeine
- Antiemetics
NSAIDs.
Non-steroidal anti-inflammatory drugs (NSAIDs) decrease prostaglandin response (which contributes to inflammation), they also decrease platelets aggregation.
- Given as an anti-inflammatory
- Given as an antipyretic
- Given as an analgesic
Common Side Effects of NSAID use.
- Nausea
- Easy Bruising
- Vomiting
- Diarrhea
- Tarry stools
- Coffee ground emesis
- Dizziness
- Liver Failure
Which patients should avoid NSAID usage?
-Patients with peptic ulcer disease (increases risk of GI bleed)
-Patients with asthma or pulmonary disease (increased risk of bronchospasm)
-Patients with pre-existing clot history such as; DVT, MI, CVA(increases risk for thrombosis)
-
Mecanisme of Action: Tylenol
Acetaminophen has analgesic and antipyretic properties. However, acetaminophen lacks peripheral anti-inflammatory properties. Instead, it inhibits the COX pathway in the central nervous system but not peripheral tissues.
Psychiatric Disorders.
disorders characterized by a change in thoughts, moods or behaviour which interferes with the person’s life.
Hallucinations.
An experience involving the apparent perception of something not present.
Two Categories of Hallucinations.
- Visual hallucinations: involve seeing things that aren’t there. The hallucinations may be of objects, visual patterns, people, or lights. For example, you might see a person who’s not in the room or flashing lights that no one else can see.
- Neuronal Dysfunction: Certain hallucinations are caused by neuronal overstimulation or neuronal damage!
* we classify hallucinations based on the sensory classification: visual, auditory, tactile or olfactory *
Delusions.
A person cannot tell what is real from what is imagined. The main feature of this disorder is the presence of delusions, which are unshakable beliefs in something untrue.
Etiology of Delusions.
Delusions can be triggered by sleep disturbance and extreme stress, but they can also occur in physical conditions, including brain injury or tumour, drug addiction and alcoholism.
Psychosis.
Hallucinations, delusions ack of awareness and judgement, mood alterations