block b lecture 1 Flashcards
autonomic nervous system
the sympathetic nervous system is a ‘what’ type of system
emergency
what division does the fight or flight reaction belong to
sympathetic
in what conditions, actions of the parasympathetic system predominate
non stressful
what effects predominate during the in between times of rest and repair
parasympathetic
3 things that the parasympathetic system do in the body
slows the heartbeat
promotes digestion
gland secretion
what are the most common receptors of the ANS
G-protein coupled receptors
what do nicotinic ion channel receptors mediate
mediate the action of released transmitters
4 major types of intracellular signalling
-ligand gated ion channels
-G protein coupled receptors
-kinase linked receptors
-nuclear receptors
what does the binding of an agonist to the receptor cause (ligand gated ion channels)
caused depolarisation
what does the binding of a ligand to G protein-coupled receptors cause
the formation of second messengers
promoting activation of protein kinases
what does the binding of a ligand to kinase linked receptors cause
activates a kinase which is part of the receptor
these kinases phosphorylates proteins on tyrosine residues to activate them
causing cascade
what does the binding of a ligand to nuclear receptors result in
formation of a complex that moves to the nucleus and functions as a transcription factor to turn on or off genes
names of two ANS receptors
acetylcholine and noreadrenaline
second messengers link the receptor to functional outcomes important to what receptors in the heart
ANS-beta 1
beta 2 receptors cause relaxation of airway vessels via what
cAMP
alpha 1 receptors in vascular smooth muscle cause what
contraction
2 types of a-adrenoceptors
a1
a2
what are a1 at sympathetic neuroeffector synapses
postsynaptic
what are a2 at sympathetic neuroeffector synapses
presynaptic
2 types of b-adrenoceptors
b1
b2
where do b1 work
heart ,intestinal smooth muscle
where do b2 work
bronchial, vascular and uterine smooth muscle
2 types of acetylcholine receptors
nicotinic and muscarinic
where are nictotinic acetylcholine receptors
in sympathetic and parasympathetic ganglie
where are muscarinic acetylcholine receptors
parasympathetic neuroeffector synpases
what are sympathomimetics
drugs that mimic noradrenaline and adrenaline
what do b2 agonists cause and used for
bronchial dilation
used to treat asthma
what are b1 agonists sometimes used to stimulate
force of heart contraction
what are a1 agonists used to treat
blocked nose/sinus
what are a2 agonists centrally acting
hypotensive drugs
what type of agonist is salbutamol
partial agonist
drug name of a-adrenoreceptor antagonist
prazosin
what do a1-adrenoreceptor blockers reduce
arteriolar and venous tone
drug name of b-adrenoreceptor antagonist
atenolol
what do b1-adrenoceptor reduce
rate and force of contraction of heart with less effect on blood vessles and bronchioles
