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Chap. 6
51
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Not Applicable
10/17/2007

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Term
What are the numerous bead like enlargments where neurotransmission takes place on adrenergic neurons?
Definition
varicosities
Term
What is the rate limiting step in the formation of norepinephrine?
Definition
hydroxylation of tyrosine by tyrosine hydroxylase to form DOPA (Dihydroxyphenylalanine)
Term
What do you get when you methylate epinephrine in the adrenal medulla?
Definition
norepinephrine
Term
In what cells are norepinephrine and epinephrine stored in the adrenal medulla?
Definition
chromaffin cells
Term
What is the product of dopamine being hydroxylated by the enzyme dopamine Beta hydroxylase?
Definition
norepinephrine
Term
What drug blocks the Magneisum cation/adenosine triphosphate (ATP)-dependent transport of biogenic amines, norepinephrine, dopamine, and serotonin from the cytoplasm into storage vesicles in the adrenergic nerves of all body tissues?
Definition
reserpine
Term

What causes vesicles inside the neuron to fuse with the cell membrane and expel their contents into the synapse? 

Definition
An action potential arriving at the nerve junction triggers an influx of Calcium ions from the extracellular fluid into the cytoplasm of the neuron.  The increase in calcium causes the vessicles to fuse with the cell membrane and expel their contents into the synapse.
Term
What type of antidepressants inhibit the reuptake  of norepinephrine by the sodium potassium activated ATPase?
Definition
tricyclic antidepressants like cocaine or imipramine
Term
What are vanillylmandelic acid, metanephrine, and normetanephrine?
Definition
The inactive products of norepinephrine oxidized by Monoamine oxidase and excreted in the urine.
Term
What type of receptors does phenyleprine have greater affinity for?
Definition
alpha 1
Term
What type of receptors does clonidine bind to?
Definition
alpha 2
Term
Which type of alpha receptors has the effects of substrates binding at them mediated by inhibition of adenylyl cyclase and a fall in the levels of cAMP?
Definition
alpha 2
Term
Which class of receptors react more strongly with isoproterenol?
Definition
Beta receptors
Term
What type of Beta receptor has a higher affinity for epinephrine than norepinephrine? 
Definition
Beta 2, Beta 1 receptors have fairly equal affinity for norepinephrine and epinephrine.
Term
What enzyme does binding at the Beta 1 or Beta 2 receptor activate?  What is the result?
Definition

Adenylyl cyclase, the activation of which results in higher concentration of cAMP in the cell

Term
What type of receptor predominates in the vasculature of the skeletal muscle?
Definition
Beta 2 predominately, but alpha 1 receptors are present
Term
What type of receptor predominates in the heart?
Definition
Beta 1
Term
How do catecholamines and noncatecholamines differ?
Definition

Non catecholamines lack the hydroxyl group on the benzene ring and have longer half lives

Term
What increases the Beta affinity of an andrergic antagonist?
Definition
The amount of bulk and substitution on the amine nitrogen.  E.g. Isoproterenol binds tightly to Beta receptors due to the bulk, whereas it doesn't bind to alpha receptors.
Term
How do indirect adrnergic agonist work?
Definition
They are taken up by the presynaptic neuron and stimulate the release of more norepinephrine.
Term
How does epinephrine effect the heart?
Definition
increase systole and decrease diastole
Term
What effect does epinephrine have on heart contraction and peripheral resistance?
Definition
increase force of contraction with decreased peripheral resistance
Term
How does epinephrine reduce IOP in glaucoma?
Definition
reduces the production of aqueous humor by vasocontrstriction of the ciliary body blood vessels
Term
How does epinephrine augment the duration of local anesthesia?
Definition
It constricts the blood vessels thus keeping the anesthetic from being absorbed into the blood and transported to be inactivated.
Term
How does norepinephrine effect blood pressure?
Definition
It increases both systolic and diastolic blood pressure
Term
Why does norepinephrine cause more vasoconstriction than epinephrine and why is it not useful in the treatment of asthma?
Definition
Noepinephrine by definition has a weak Beta 2 activity.  Epinephrine induces compensatory vasodilation via Beta 2 receptors of blood vessels supplying skeletal muscles, norepinephrine does not.
Term
What effect does pretreatment of atropine have on norepinephrine stimulation?
Definition
tachycardia
Term
Why is dopamine superior to norepinephrine in the treatment of shock?
Definition
Dopamine does not decrease blood supply to the kidney and contribute to renal shutdown. 
Term
Which alpha receptors does phenylephrine bind?
Definition
alpa 1
Term
Does phenylephrine effect the heart?
Definition

No, but it causes reflex bradycardia when given parenterally

Term
How does phenylephrine effect the sinuses?
Definition
It's a decongestant
Term
How does phenylephrine effect the blood vessels?
Definition
it's a vasoconstrictor
Term
What effect does phenylephrine have on systolic and diastolic blood pressures?
Definition
Like norepinephrine, it raises both systolic and diastolic blood pressure
Term

What effect can phenylephrine have on tachycardia?

Definition
Phenylephrine can be used to terminate episodes of supraventricular tachycardia.
Term
What advantage does methoxamine have over other adrenergic drugs?
Definition
It doesn't trigger cardiac arrhythmias
Term
What is the pulse in bradycardia?
Definition
less than 60
Term
What is the pulse in tachycardia?
Definition
over 100
Term
What type of patient would you give a partial Beta agonist?
Definition
a patient with bradycardia pindolol or acebutolol
Term
What type of drug improves chest pain and angina by putting  a governor on the pulse?
Definition
Beta 1 selective blocker such as MAAE

Metoprolol
Atenolol
Acebutolol
Esmolol
Term
What effect do beta blockers have on cholesterol?
Definition

Cholesterol of 180-185 will increase to 205 on a nonselective beta blocker

Term
What do acebutolol, practolol, alprenolol, carteolol, oxprenolol, penbutolol, and pindolol all have in common?
Definition
They all  posses partial beta 1 agonist activity.
Term
How do MAOIs work?
Definition
Normally monoamine oxidase breaks down norepinephrine that is reabsorbed by the presynaptic axon into different metabolites.  Monoamine oxidase inhibitors stop norepinephrine breakdown in the presynaptic axon and thus leave more norepinephrine around to be stored in vesicles and released.
Term
How does reserpine work?
Definition
Reserpine stops norepinephrine from entering the vessicles. 
Term
How does guanethidine work?
Definition
Guanethidine stops the vessicles from being released. 
Term
How does cocaine work?
Definition
It blocks alpha 2 receptors leaving more norepinephrine in the synaptic cleft and thus increases Beta receptor activation due to blocking of alpha 2 receptors
Term
Why would a phenylephrine drop without punctal occlusion be mildly contraindicative to a patient on reserpine or guanethidine?
Definition
Reserpine and guanethidine up regulate or sensitize the receptors by decreasing the amount of norepinephrine around.  A little bit will double the receptor response and thus increase blood pressure and increase pulse.
Term
Is Na an extracellular or intracellular compound and what is its concentration in the blood?
Definition
extracellular, 125-140 mmol
Term
What is the sodium concentration of saline solution?
Definition
0.9%
Term
Is potassium an intracellular or extracellular compound and what is its concentration normally?
Definition
Intracellular, 3.5 to 4.0 mmol
Term
What do you call increased uric acid in the plasma and what does it cause?
Definition
hyperurecemia, It causes gout
Term

What do you call decreased plasma volume which equal decresed blood volume which equals dehydration?

Definition
hypovolemia
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