48 terms

Lippincott: Adrenergic

Tyrosine is hydroxylated to dihydroxyphenylalaine (DOPA) by what enzyme?
Tyrosine hydroxylase
What is the rate limiting step in synthesis of NE?
Synthesis of DOPA by tyrosine hydroxylase
Reserpine blocks what?
Guanethidine blocks what?
NE release
Cocaine and tricyclic antidepressants blocks what?
NE reuptake
EPI prefers alpha or beta receptors?
Alpha 1
Alpha 2
Alpha 1 activates what secondary enzyme
Phospholipase C - IP3 and DAG. Increases Ca
Alpha 2 activates what secondary enzyme
Inhibit adenylyl cyclase. Decrease cAMP
All B activate what secondary enzyme?
Activates adenylyl cyclase, increases cAMP
Beta 2 has higher affinity for NE or EPI?
Which adrenoceptor?Vasoconstriction, increased TPR, increased BP, mydriasis, increased closure of internal sphincter of the bladder
Alpha 1
Which adrenoceptor? Inhibition of NE release, inhibition of ACh release, inhibition of insulin release?
Alpha 2
Which adrenoceptor? Tachycardia, increased lipolysis, increased myocardial contractility, increased renin release
Beta 1
Which adrenoceptor? Vasodilation, slightly decreased peripheral resistance, bronchodilation, increased release of glucagon, increased muscle and liver glycogenolysis
Beta 2
Substitution on what increases affinity for beta receptors?
Substitution on the amine nitrogen
What are the four catecholamines?
Epinerphrine, Norepinephrine, dopamine, and dobutamine
How does epi affect systolic and diastolic pressures?
Increases systolic, decreases diastolic
How does epi affect cardiovascular?
Positive inotropic (contractility) and rate (chronotropic) via Beta 1.
How does EPI affect diabetics?
Significant hyperglycemia effects
Anaphlactic shock is what type of hypersensitivit?
Type 1 hypersensitivity
How does NE affect systolic and diastolic pressures?
Increases both
How does NE affect peripheral resistance?
Constricts all blood vessels, causing increased peripheral resistance
How does EPI affect peripheral resistance?
Vasodilates, decreases it
How does NE affect baroreceptor?
Reflex bradycardia
What receptors does isoproterenol affect?
Beta 1 and 2
How does isoproterenol affect rate and contraction of heart?
Increases both.
How does isoproterenol affect systolic and diastolic pressure?
Moderate increase in systolic, markedly decrease in diastolic pressure.
How does isoproterenol affect peripheral resistance?
Significant decrease (hence decrease in diastolic pressure)
Raises blood pressure by stimulating Beta 1 and alpha 1 vasoconstriction, but also enhances perfusion to the kidney and splanchnic areas.
What is dobutamine used for? What receptor?
Increase cardiac output in congestive heart failure. Beta-1
Dobutamine should be used with caution in what types of patients? Why?
Atrial fibrillation patients. Drug increases atrioventricular conduction.
Nasal decongestant, terminate episodes of supraventricular tachyardia.
Phenylephrine (alpha-1 agonist)
Used for attacks of paraoxysmal supraventricular tachycardia
Alpha 2
HTN and for withdraw from opiate drugs
Beta 2 agonist
Nocturnal asthma
Salmeterol and formoterol
What are three main indirect-acting adrenergic agonists?
Amphetamine, tyramine, and cocaine
Found in ripe cheese and wine
Enter nerve terminal and displace stored NE
Block Na/K ATPase for reuptake
Name two main mixed-action adrenergic agonists.
Ephedrine and pseudoephedrine
Which one has less CNS effect? Ephedrine and pseudoephedrine?
What receptor on ciliary eye muscle?
Beta 2
What drug can be used to increase cardiac output without significant increase in heart rate?
Dobutamine (only beta 1)
Mydriasis, what receptor?
Alpha 1