Exam 5 - Vasoconstrictors Hockerman Flashcards
what is MLCK activated by?
calmodulin in response to inc in calcium
endogenous peptide vasoconstrictors (4)
angiotensin
vasopressin
endothelin
urotensin
(first 3 are most important)
which endogenous vasoconstrictor binds to GPCRs in vasc sm muscle and cardiac muscle and is elevated in diabetics?
a. angiotensin
b. vasopressin
c. endothelin
d. urotensin
d. urotensin
where is urotensin produced? (3 places)
heart, liver, kidney
which endogenous vasoconstrictor binds to GPCRs in vasc sm muscle and is elevated in PAH?
a. angiotensin
b. vasopressin
c. endothelin
d. urotensin
c. endothelin
vasoconstrictors treat hypotension that is caused by what 3 things?
shock
anesthesia (especially spinal)
chronic orthostatic hypotension
epinephrine, phenylephrine, midodrine, and droxidopa are
a. alpha 1 agonists
b. alpha 2 agonists
c. alpha 1 antagonist
d. alpha 2 antagonist
e. beta 1 antagonist
a. alpha 1 agonists
for control of blood flow (reduction), what drug is given as adjunct to local anesthetics?
epinephrine
what two drugs can be used for hemostasis during surgery?
epinephrine, cocaine
which of the following alpha 1 agonists are direct-acting agents? SELECT ALL THAT APPLY
a. phenylephrine (neosynephrine)
b. ephedrine
c. oxymetazoline (Afrin, Visine)
d. pseudoephedrine (Sudafed)
e. tetrahydrozoline (Visine)
f. naphazoline (Privine)
a
which of the following alpha 1 agonists are indirect-acting agents? SELECT ALL THAT APPLY
a. phenylephrine (neosynephrine)
b. ephedrine
c. oxymetazoline (Afrin, Visine)
d. pseudoephedrine (Sudafed)
e. tetrahydrozoline (Visine)
f. naphazoline (Privine)
b, d
which of the following alpha 1 agonists are partial agonists? SELECT ALL THAT APPLY
a. phenylephrine (neosynephrine)
b. ephedrine
c. oxymetazoline (Afrin, Visine)
d. pseudoephedrine (Sudafed)
e. tetrahydrozoline (Visine)
f. naphazoline (Privine)
c, e, f
why can epinephrine be used for anaphylactic shock?
primarily due to stimulation of alpha and beta receptors, blocks histamine release
phospholipase C role in vasoconstriction stimulated by alpha 1 agonists (this was a learning objective)
-PLC is activated by Gq
-PLC converts PIP2 into IP3 and DAG (2nd messengers)
-IP3 induces calcium release from stores, which will bind to calcium to become active
-calmodulin can then regulate activity of MLCK, eventually leading to contraction
