Pharmacology of the Central Nervous System Flashcards
What are the key regions in the brain
Cerebral hemispheres, diencephalon (& subcortical region), Brain stem (Midbrain, pons, medulla), cerebellum
Function and role of key structures within in brain
What does the cerebral cortex contain and what are its functions?
Frontal Lobe: contains the primary cortex, controls voluntary movements of specific body part. Contains most the dopamine-sensitive neurons in the cerebral cortex
Parietal Lobe: integrates sensory information , major sensory inputs from the skin and relay to the parietal lobe
Temporal Lobe: processes sensory input (auditory and visual), key role in the formation and retention of visual memory, language comprehension and emotion association
Occipital Lobe: the visual processing center and contains the primary visual cortex
What is the function and role of the subcortical region of the brain
Thalamus: acts as relay/gateway between incoming sensory pathways and the cortex
Hypothalamus: integrating region for the autonomic nervous system, regulates body temp, blood pressure, sleep and emotions
Limbic System: supports a variety of functions including emotion, behavior, motivation, long-term memory and olfaction
What does the hind brain contain and what is there functions?
Pons: coordination center for signals and communications that flow between the two brain hemispheres and the spinal cord
Cerebellum: Automatic processing centre. Adjusts voluntary and involuntary motor activities based on sensory input and stored memories.
Medulla Oblongata: Contains control centers for autonomic vital functions heart rate, blood pressure, breathing.
What are the regions of the spinal cord?
8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
What is the neuroglia?
Non-neuronal cells that maintain homeostasis, from mylein anf provide support and protection for neurons in the CNS
What are the main functions of the glial cells?
Maintain the blood-brain barrier, supply nutrients and oxygen to neurons, insulate one neuron from another, destroy pathogens and remove dead neurons, reduce and curculate cerebrospinal fluid
What is the blood brain barrier and its functions?
Tightly regulated interface in the CNS that regulates the exchange of molecules in and out from the brain this maintaining homeostasis
What are the primary neurotransmitters in the CNS?
Acetylcholine, dopamine, noradrenaline, serotonin, glutamate, GABA
What are the fundamentals of neural signaling
Neurotransmission , resting potential, action potential, signal propagations
How can signaling occur in the CNS?
Neuron to neuron,
Multi-neuron synapsing
Neuroplasticity (ability of the brain to change)
5 main NT classes (& myriad of individual NTs)
What is involved in Synapsing in the CNS?
Neurons in the CNS often receive multiple inputs the must be processed and integrated for successful transfer of information. Axon can synapse into a dendrite, onto a cell body or onto axon, as well as into the blood stream to diffuse into adjacent nervous tissue
What does excitatory neurotransmitter do?
Leads to changes that generate an action potential in the responding neuron
What does an inhibitory neurotransmitter do?
tend to block the changes that cause an action potential to be generated in the responding cell
What are the two classes of receptors in CNS?
Ligand-gated ion channels and G protein-couple receptors (GPCR)
What is Dopamine’s receptor type and receptor subtype?
Subtype - D1-D5
Receptor Type - G couple protein
What is Noradrenaline and Adrenaline’s recpetor type and subtype?
Subtype- Alpha and beta
Receptor type - G protein-coupled
what is serotonins receptors subtypes and types?
Subtype- 5HT 1A - 1D, 2A-2C 5-7 & 5-HT3
Type- G protein couple except 5-HT3 which is Ligand gated ion channel
What is acetylcholine receptors subtypes and types?
Subtype = Muscarinic (type - G protein coupled), Nicotinic ( Type- Ligand Gated Ion channel)
What is glutamate receptor subtypes and types?
Subtype - NMDA, AMPA, Kainate (Type - Ligan Gated ion channels), MgLuR1-8 (Type- G protein coupled)
What is GABAs receptor types and subtypes?
Subtype - A & B
Type - A : Ligand gated ion channel
B: G protein coupled
What role does Acetylcholine play as a neurotransmitter and what are its functions in the CNS?
Has cholinergic fibers widely distributed through the cerebral cortex, cerebellum, and spinal cord.
Functions: Sleep/wake cycles, arousal, respirations, vertigo, memory, attention. A role in extrapyramidal motor systems/responses and side effects. Role in the vestibular system (spatial orientation)
What are the cholinergic receptors?
Nicotinic cholinergic, Muscarinic cholinergic
What are monoamine neurotransmitters?
neurotransmitters that share a common structure and form a family of neurotransmitters.
Catecholamines : Dopamine , noradrenaline, adrenaline
Indolamines: Serotonin
What are monoamine neurotransmitters?
neurotransmitters that share a common structure and form a family of neurotransmitters.
Catecholamines : Dopamine , noradrenaline, adrenaline
Indolamines: Serotonin
What are the functions of the neurotransmitter dopamine?
Initiation and execution of movement, emotions and organization of thoughts
What disease/disorders are associated with the neurotransmitter Dopamine?
Parkison disease, schizophrenia and affective disorders.
What are the functions of the neurotransmitter noradrenaline?
Behavioral arousal and levels of awareness
What are the diseases/disorders associated with the neurotransmitter noradrenaline?
Depression, anxiety, and panic disorder
What is the function of the neurotransmitter Serotonin & what disease/ disorders are associated with it?
Ascending system: promotion of sleep in determining mood and in mental illness.
Depression, emesis
What is the functions of the neurotransmitter Acetylcholine? And what disease/disorders are associated with this?
Primary in interneurons, Alzheimer disease, amyotrophic lateral sclerosis, Huntingtons disease
What is the functions of the neurotransmitter Glutamate? And the diseases/disorders associated with it?
Major Excitatory in CNS, Epilepsy, schizophrenia
What are the functions of the neurotransmitters GABA? And the disease/disorders associated with this?
Most inhibitory action in CNS, Huntingtons Disease
What are the functions of the neurotransmitter Glycine?
Inhibitory motor control in spinal cord
What are the modulatory neurotransmitters?
Dopamine, Noradrenaline, Serotonin, Acetylcholine
What are the excitatory neurotransmitters?
Glutamate
What are the inhibitory neurotransmitters?
GABA, Glycine
How is Dopamine related to schizophrenia?
Defective dopamine neurotransmission. Increase in DA function in the mesolimbic system
Decreased function in the mesocortical DA system
How is Dopamine related to schizophrenia?
Defective dopamine neurotransmission. Increase in DA function in the mesolimbic system
Decreased function in the mesocortical DA system
How is dopamine involved in Parkinson’s disease? What is the therapeutic approach?
DA neurons in nigrostriatal pathway degenerate , Replacing DA is a therapeutic aprroach to treat PD
What are extrapyramidal Symptoms?
Are drug induced movement disorders from the extrapyramidal system
Describe depression and its causes, antidepressants (treatment) and how the CNS impacts it
Depression: Loss of pleasure or interest in usual activities
Causes: depression appears to involve the development of low levels of monoamine neurotransmitters Serotonin (5HT) and noradrenaline (NA)
Treatment: antidepressant drugs act to increase 5HT (Serotonin) and/or NA (Noradreanline) levels
In terms of antidepressants how does increasing noradrenergic and serotonergic signaling work?
Blocks the noradrenaline or serotonergic reuptake transporters
and inhibit the catabolism of noradrenaline and serotonin
What are Tricyclic Antidepressants mechanisms of action, Autonomic effect and agents
MOA: Blockage of reuptake increases NA and 5HT levels and stimulation of NA and 5ht receptors
Autonomic Effects: Anticholinergic activity can cause dry mouth, constipation, and urinary retention, Alpha blocking activity can lower blood pressure , may effect cardia rhythm and cause cardiac arrythmias.
Agents: Amitriptyline (Elavil) ETC
What are the Monoamine Oxidase Inhibitors mechanisms of action and agents
Monoamine oxidases (MAO) catabolizes NA and 5HT. Inhibition increases NA and 5HT levels and stimulation of NA and 5HT receptors
Should avoid foods containing tyramine, can cause a hypotensive crisis
Used for pts who cant tolerate TCAs and SSRIs
Agents: Phenelizine (nardii)
What are the Monoamine Oxidase Inhibitors mechanisms of action and agents in terms of antidepressants
Monoamine oxidases (MAO) catabolizes NA and 5HT. Inhibition increases NA and 5HT levels and stimulation of NA and 5HT receptors
Should avoid foods containing tyramine, can cause a hypotensive crisis
Used for pts who cant tolerate TCAs and SSRIs
Agents: Phenelizine (nardii)
What is Selective Serotonin Reuptake Inhibitors (SSRIs) in terms of antidepressants
Most prescribes class of antidepressants
Selectively block reuptake of 5HT, increases levels of receptor stimulation. Cause little if any anticholinergic and alpha blocking effects
What is Serotonin-noradrenaline Reuptake inhibitors (SNRIs) in terms of Antidepressants
Block reuptake of both NA and 5ht. effective for severe depression
Define Schizophrenia the causes and treatment
Definition: psychotic illness characterized by multiple symptoms affecting thought, percetion, emotion and volition. 2 classes Positive includes delusion, hallucinations Negative poverty of speech flat emotions.
Cause; Excessive dopaminergic activity
Treatment: Anti-psychotic drugs that have inhibitory effects on D2 receptors and occasionally D4 receptor
What are the side effects of Anti-psychotic drugs?
Drugs can control ‘positive’ features of the disease but have little effect on the ‘negative’ features.
Define what Parkinsons disease is and the treatment involved
neurological movement disorder of the brain involving the basal ganglia. Pathophysiology includes loos of dopaminergic neurons in substantia nigra. Major cause is a deficiency of the inhibitory neurotransmitter dopamine and the resulting excessive activity of the excitatory neurotransmitter acetylcholine
Treatment: Primary therapy is the administration of drugs that increase the levels of DA or DA activity in the basal ganglia
secondary treatment is administration of anticholinergic drugs that decrease ACh activity in the basal ganglia
Define Epilepsy
a chronic disease in which seizures result from the abnormal high frequency discharge of neurons, starting focally and spreading to affect other parts of brain
What are the mechanisms of an anticonvulsant (antiepileptic) drugs
Enhancement of inhibitory synaptic transmission(GABA)
Modulation of Ion channels to dimish generation of action potential : - Voltage-dependent sodium channels, calcium T-channels
Inhibition of excitatory glutamate transmission
Define dementia and Alzheimer’s Disease
dementia is a progressive failure of many cerebral functions, Alzheimer’s disease is the most common form dementia
What is the treatment of Alzheimer’s?
The primary goal of therapy is to treat and manage the patient symptoms
