Cardio 3 Flashcards
the primary nerve of the Para sym NS is
the vagus nerve
the para syn NS is a projection of the
cranial and sacral nerves
para syn NS has what type of firing rate
-this slows the heart rate
tonic firing rate
what nerve releases Ach
vagus nerve
2 main receptors for Ach
nicotinic receptor and muscarinic receptor
The vagus nerve releases Ach.
-Ach binds to what receptors?
-these receptors are on what type of nerves?
ACH binds to nicotinic receptors
nicotinic receptors are on the post ganglionic nerves
PRE ganglionic nerves start at the X
they synapse onto the X
they start at the CNS
they synapse into the post ganglia nerves withing the ganglia
POST ganglionic nerves start at the X
they synapse onto the X
start at the ganglia
they synapse onto the targeted organs
4 things the sympathetic nerves stimulate:
- heart
- arteries
- veins
- adrenal glands
NTs used in the symp NS (3 total)
Ach
epinephrine/ norepi
what NT is used when synpase between pre and post ganglions?
Ach
what NT is exclusively used when synapsing from post gang to target organ
Epinephrine/norepi
-note: ach can also be used for parasympathetic
BUT epi/norepi is never used from pre to post ganglion
2 types of adrenergic RECEPTORS
alpha
beta
alpha adrenergic receptors are found in the
heart
beta adrenergic receptors are found in the
heart and lungs
2 types of beta adrenergic receptors
-where are they and what do they do?
Beta 1
-found in heart
-increase HR, increase contractile strength
Beta 2
- found in lungs
-increase in bronchodilation
the vagus nerve stimulates what nodes
SA and AV nodes
the only way to reduce HR is to reduce the X and X of APs
frequency and conduction
the muscular components of the heart are modulated by what 2 types of nerves?
Adrenergic and vagal nerves
-Adrenergic - increase HR
-Vagal - decrease HR
in Vagal innervation, muscarinic receptors are X protein coupled receptors?
what does this mean?
muscarinic receptors are G coupled protein receptors
this means when Ach binds to the muscarinic receptor, it activates the G protein in the cell
2 functions of G inhibitory protein
-reduce cAMP
-hyperpolarize cell
When vagal intervention causes inhibition, what main 2 factors are decreased?
- decrease in chronotropy
-decrease in dromotropy
over activation of the sym NS is called
tacicardia
what NT has a higher affnity for B1 receptors?
NE
B1 receptors are found in the
heart
when activated, B1 receptors increase the activity of what type of channels?
Ca
-used for heart muscle contraction
beta receptors are what type of protein coupling
G protein coupling receptors
when NE or EPI bind to the B1 receptor, what G protein is activated?
-what 2 factors are activated?
G stimulatory
-causes depolarization
- increases cAMP
and PKA
the sympathetic NS causes increase or decrease in the 4 factors?
increase
parasympathetic NS causes increase or decrease in the 4 factors
decrease
alpha receptors are found..
beta receptors are found..
- Found predominantly in the smooth muscle cells of arteries and veins.
- Beta one is mostly in heart
- beta 2 in Lungs, skeletal muscle, arteries
which Nervous System is the main play in determining vasomotor control
sympathetic
)
activation of what gland causes release of NE and EPI
whats the raio?
adrenal glands
80:20
EPI:NE
EPI acts on what receptors?
B2 receptors
NE acts on what receptors?
a1 receptors
a1 receptors are stimulated by what NT?
NE
b2 receptors are activated by what NT?
EPI
when NE acts on the a1 receptors, what occurs to the arteries and veins?
constriction
-a1 receptors also activate what pathway
IP3 pathway
-causes increase in intracellular ca
-causes vasocontriction
When EPI binds to B2 receptors, what happens to the arteries and veins?
Vasodilation
activation of a1 receptors cause what to happen to the vessels?
contriction
activation of b2 receptors cause what to happen to the vessels?
dilation
