Step 1 - Pharm diagrams

denniskwinn's version from 2015-04-25 18:06

Adrenergic receptors

ReceptorAgonist potencyagonist actionmechanismAgonistsAntagonists
α1NE>epi>>isoprenalinevascular, pupillary, intestinal and bladder sphincter smooth muscle contractionGq: phospholipase C activated - IP3 and Ca increaseNE, Phenylephrine, Methoxamine, Cirazoline, xylometazolinePrazosin, Tamsulosin, Terazosin, Amitryptiline, Clomipramine, Doxepin, Trimipramine
α2Epi>NE>>IsoprenalineSmooth muscle relaxation, decrease sympathetic outflow and insulin releaseGi -adenylate cyclase inactivated, cAMP downClonidinePhentolamine, Yohimbine, Idazoxan, Mirtazapine
β1Isoprenaline>Epi>NE↑HR, ↑Contractility, ↑renin release, ↑lipolysisGs - activated adenylate cyclase=↑cAMPNoradrenaline, Dobutamine, IsoprenalineMetoprolol, Atenolol etc.
β2Isoprenaline>epi>NEvasodilation, bronchodilation, ↑HR, ↑contractility,↑lipolysis,↑insulin release, ↓uterine toneGs: adenylate cyclase activated, cAMP upShort: Metapoterenol, Albuterol Long: Salmetrol. Terbutaline and Ritodrine for premature uterine contratctionsButaxamine, Propanolol

Potency vs Efficacy



Question Answer
AEfficacy; Maximum effect a grug has at a givan dose
BPotency; Amount of drug needed to produce effect
CFull agonist with maximum effect
DSame "Potency" as "C" with decreased efficacy (C + Non-competitive antagonist= decreased Vmax with same Km)
ESame "Efficacy" as "C" with decreased potency (C + Competitive antagonist= Vmax is the same but requires higher doses tp overcome antagonist, increased Km)
FPartial agonist; [Decreased efficacy and increased potency] (Partial agonists will ALWAYS decrease Vmax and Km, Potency may change)
GPartial agonist; [Potency independent] (ALWAYS decrease Vmax, in this case Km is increased)
HDecreased "Efficacy"; (Effect of agonist)
IIncreased Potency; (lower Km)
JDecreased Potency; (higher Km) This could be the effect of an agonist.

Enzyme kinetics of competitive and noncompetitive inhibition

Question Answer
B1/2 Vmax
D1st order kinetics (Most drugs)
EZero order kinetics (Peas & WHEATS= Phenytoin/Phenylbutazone, Warfarin, Ethanol, Aspirin, Theophylline/Tolbutamide, Salicylates) *Phenytoin, Warfarin, Ethanol, Aspirin
FNo inhibition
GCompetitive inhibition (Same Vmax, Increased Km, can be overcome with increased concentration of drug)
HNon-Competitive inhibition (Same Km, decreased Vmax, cannot be overcome)

Enzyme kinetics of competitive and noncompetitive inhibition

Question Answer
ASame Vmax; must be No inhibition + Competitve inhibition
BDecreased Vmax; must be NON-competitive
CSame Km; must be NO inhibition and NON-competitive
DIncreased Km; must be competitive
FNo inhibition line
GCompetitive inhibition line
HNON-competitive inhibition line