Difference between revisions of "Adrenergic Pharmacology"

Revision as of 06:07, 4 February 2023

Adrenergic Receptors
Receptor	Binding Affinity	Effects	Mechanism	Agonists	Antagonists
α1	NE > Epi >> Iso	Smooth muscle contraction, ↑SVR, ↑MAP Mydriasis, urethral sphincter contraction	G_q → PLC → IP₃/DAG → [Ca²⁺]_i	NE Phenylephrine (pure α1) Midodrine	α1 selective: Prazosin Tamsulosin
α2	Epi = NE >> Iso	↑SVR, ↑MAP Decreased insulin release, inhibits lipolysis, decreases aqueous humor production	presynaptic G_i → ↓AC → ↓cAMP → inhibition of NT release, sympatholytic effects	Dexmedetomidine Clonidine	Non-selective: Phenoxybenzamine Phentolamine Trazodone
β1	Iso > NE > Epi	↑Chronotropy (myocytes), ↑Inotropy (SA node) →↑CO ↑Renin release/↑volume (JGA) Amylase secretion	G_s → ↑AC → ↑cAMP	Dobutamine Isoprenaline Norepi	Cardiac Selective: Metoprolol Atenolol Esmolol
β2	Iso > Epi > NE	Smooth muscle relaxation	Gs, cAMP up	Albuterol Formoterol Isoprenaline Salmeterol Terbutaline Ritodrine	Non-Selective: Propranolol Nadolol Pindolol Timolol Carvedilol (anti-α1) Labetalol (anti-α1)
β3	Iso > Epi = NE	Lipolysis, bladder detrusor relaxation	Gs, cAMP up	Mirabegron	SR 59230A

@@ Line 4: / Line 4: @@
 ! Receptor !! Binding Affinity !! Effects !! Mechanism !! Agonists !! Antagonists
 |-
-| &alpha;1 || NE > Epi >> Iso || Smooth muscle contraction || Gq, PLC -> IP3/DAG
+| &alpha;1 || NE > Epi >> Iso
+|
+*Smooth muscle contraction, &uarr;SVR, &uarr;MAP
+*Mydriasis, urethral sphincter contraction
+|
+G<sub>q</sub> &rarr; PLC &rarr; IP<sub>3</sub>/DAG &rarr; [Ca<sup>2+</sup>]<sub>i</sub>
 |
 *NE
-*Phenylephrine
+*Phenylephrine (pure &alpha;1)
 *Midodrine
 |
@@ Line 14: / Line 19: @@
 *Tamsulosin
 |-
-| &alpha;2 || Epi = NE >> Iso || Mixed effects || Gi, presynaptic, cAMP down
+| &alpha;2 || Epi = NE >> Iso
+|
+*&uarr;SVR, &uarr;MAP
+*Decreased insulin release, inhibits lipolysis, decreases aqueous humor production
+|
+presynaptic G<sub>i</sub> &rarr; &darr;AC &rarr; &darr;cAMP &rarr; inhibition of NT release, sympatholytic effects
 |
 *Dexmedetomidine
@@ Line 24: / Line 34: @@
 *Trazodone
 |-
-| &beta;1 || Iso > NE > Epi || Chronotropy, Inotropy, Amylase secretion || Gs, cAMP up
+| &beta;1 || Iso > NE > Epi
+|
+*&uarr;Chronotropy (myocytes), &uarr;Inotropy (SA node) &rarr;&uarr;CO
+*&uarr;Renin release/&uarr;volume (JGA)
+*Amylase secretion
+|
+G<sub>s</sub> &rarr; &uarr;AC &rarr; &uarr;cAMP
 |
 *Dobutamine