EXAM 2 2024 MOST RECENT UPDATE
EXAM PRATICE [MOST TESTED QUESTIONS]
COMPREHENSIVE QUESTIONS AND VERIFIED
CORRECT ANSWERS GRADED A+ GET IT RIGHT
Norepinephrine on Alpha 1 receptors
Location: blood vessel, urinary bladder, GI tract
1. Norepinephrine binds to Alpha 1 receptor
2. Activates a protein which normally exists in cytoplasm
called g-protein. G protein itself has 3 subunits: alpha,
beta and gamma (only need alpha in this case) and alpha
has 2 subunits: S (stimulator) and I (inhibitor). Activates G
protein alpha S
3. Activates phospholipase-C
4. After, it activated another enzyme IP3
5. Activates S4 (sarcoplasmic reticulum)
6. Releasing of Calcium into cytoplasm from SR
7. Concentration of Ca increases in cytoplasm then it
binds to troponin-C (activates microfilaments and causes
muscle contraction) Contraction and constriction is
purpose
Norepinephrine on Alpha 2 receptors
*Location: GI tract, fat cells, pre-synaptic compartment,
etc.
1. Norepinephrine binds to alpha-2 receptor
2. Activates G-protein Alpha I
,3. Prevents AC (adenylate cyclase)
4. Decreases intracellular energy (CAMP)
5. Inhibition occurs; relaxation or dilation of smooth muscle
Excess norepinephrine binding to alpha can cause?
Hypertension
Nervous system has 3 parts:
Motor, sensory and autonomic
ANS
Automatic processes (breathing and blood pressure) and
Innervation of internal organs in abdominal cavity, thoracic
cavity and smooth muscle of bloodless cells
Two parts of ANS
Sympathetic and Parasympathetic
Sympathetic system
This system is activated when the body is active and it
increases heart rate, increases contractility of
myocardium, relaxes m. of bronchi, contracts blood
vessels, increases blood flow, increase blood pressure,
stimulates sweat glands and inhibits digestive system
Location of Sympathetic
Spinal cord from T1-L2/L3 (Thoracolumbar) and occurs in:
heart, lung, sweat glands and blood vessels
Parasympathetic system
This system is active when you are resting ("Rest and
digest") and it decreases heart rate, decreases respiratory
system, increases digestive system, increases secretion of
gastric hormones
Location of Parasympathetic
Brain stem (CN 3, 7, 9, 10), pelvic splanchnic nerve and
sacral portion of spinal cord (S2-S4)
Sympathetic system physiological steps
,1. Pre-ganglionic
2. Sympathetic chain
3. Post-ganglionic
4. Internal organ
Norepinephrine on Beta 1 receptors
*Location: heart in SA node, AV node and myocardium
1. Norepinephrine binds to Beta-1 receptor
2. Activated G-protein alpha S
3. Activates AC
4. Increases CAMP (intracellular energy)
5. Shows its physiological reaction: increases heart rate,
contractility of myocardium and conduction velocity
(related to SA/AV nodes)
When patient has tachycardia due to exceess
norepinephrine, you can use what to decrease heart
rate?
Beta-1 blocker (called propranolol)
Norepinephrine on Beta 2 receptors
*Location: urinary bladder sphincter and respiratory
system (smooth muscle of bronchi)
1. Norepinephrine binds to Beta-2 receptor
2. Activates G protein alpha s
3. Activates AC
4. Increases CAMP
5. Effect: relaxes smooth muscle
Asthma patients use medications that affect what
norepinephrine receptor?
Beta-2 (albuterol)
Differences in sympathetic and parasympathetic
1. The pre-ganglionic fiber of sympathetic system is
shorter than parasympathetic
, 2. The pre-ganglionic fiber of parasympathetic travels
toward the wall of internal organs and then has synapse
with post-ganglionic fibers inside wall but pre-ganglionic of
sympathetic synapses with post-ganglionic fiber inside the
sympathetic chain/ganglia
3. The neurotransmitter of pre-ganglionic fiber of
sympathetic is ACH and post-ganglionic fiber of
sympathetic is norepinephrine but parasympathetic
neurotransmitters in both pre-ganglionic and post-
ganglionic is ACH
4. Name of receptor for norepinephrine is adrenergic
receptor and receptor for ACH is cholinergic receptor
(cholinergic has muscarinic and nicotinic receptors)
Adrenergic receptor
ACH Sympathetic receptor with multiple types such as
alpha and beta
Muscarinic receptor
An ACH parasympathetic receptor (ex: heart)
Nicotinic receptor
An ACH parasympathetic receptor (ex: GI tract)
Cholinergic receptor
ACH parasympathetic receptor with two types
Medulla
Respiratory, vomiting, swallowing, coughing, etc.
Pons
Pneumotaxic center
Midbrain
Urinary system
Hypothalmus
Contains many nuclei (hypothalamic nuclei) that contains
certain neurons that control many things such as: appetite,