lecture 4 - pharmacology of the peripheral nervous system 1 Flashcards
(27 cards)
what are the branches of the peripheral nervous system
- somatic - voluntary control
- autonomic - involuntary control
what is the function of the autonomic nervous system
regulate organs to maintain homeostasis
what are the branches of the autonomic nervous system
- sympathetic - fight or flight
- parasympathetic - rest and digest
what is the function of afferent autonomic nerves
pass information from the peripheral organs to the central nervous system
what is the function of efferent autonomic nerves
pass information from the central nervous system to the peripheral organs
describe the physiological responses to the sympathetic nervous system
- pupils dialate
- heart rate increase, dilation of coronary blood vessels
- bronchodilation
- BV in the skin constrict
- butterflies in the stomach
- hyper focused and racing thoughts
where do the nerves come from in the parasympathetic division
cranial and sacral areas of the spinal cord
what are the functions of the nerves in the parasympathetic division
increase body functions (digestion and elimination)
describe the nerve characteristics from the parasympathetic division
long pre-ganglion nerves, short post-ganglionic nerves
where do the nerves come from in the sympathetic division
thoracic and lumbar spinal nerves
describe the sympathetic division nerve characteristics
ganglion closer to the spinal cord, short pre-ganglionic nerve, long post-ganglionic nerves
the peripheral autonomic nerves consists of 2 fibres, what are they?
- preganglionic nerve fibres - neuron that emerge from CNS
- postganglionic nerve fibre - neurons that travel from ganglion to internal organ
describe the steps of adrenergic transmission
- the synthesis of tyrosine into DOPA which forms dopamine which forms noradrenaline
- dopamine is stored as noradrenaline in a pre-synaptic vesicle
- neurotransmitter is released from the vesicle by an action potential
- noradrenaline binds to receptor on effector organ which causes an effect on an organ
- excess noradrenaline is taken back into the nerve terminal for storage
- excess noradrenaline is broken down by MAO to form metabolites
what are the 4 types of adrenergic receptors
alpha-1, alpha-2, beta-1, beta-2
what are the locations and functions of alpha-adrenergic 1 receptors
smooth muscles of arteries and veins (vasoconstriction), pupil dilation, relax of bladder muscle (urinary retention), contract urinary sphincter
what are the functions and locations of the alpha-adrenergic 2 receptors
presynaptic membrane (inhibition of noradrenaline release)
what are the locations and the functions of beta-adrenergic 1 receptors
heart (increase force and rate of contraction) and kidney (increase renin release)
what are the locations and functions of beta - adrenergic 2 receptors
lung (bronchial relax)
what are the adrenergic drug classes and what are their functions
- sympathomometics - stimulate sympathetic nervous system
- sympatholytics - block sympathetic nervous system
what are alpha agonists indicated for the treatment of
- cardiovascular collapse
- nasal congestion
- mydriasis
- hypertension
what are the adverse side effects from taking alpha agonists
hypertension, tachycardia, angina
what are alpha antagonists indicated for the treatment of
- hypertension
- benign prostatic hypertrophy
what are the adverse side effects from taking alpha antagonists
hypotension, dizziness, nasal congestion
what are beta agonists indicated for the treatment of
- asthma
- premature labour
- severe heart failure
- anaphylaxis
- cardiac arrest
