Andrenoreceptor Agonists until Selective B-1 Flashcards
Location of Catecholamines
Sympathetic post-ganglionic neuron
Adrenal Medulla (Chromaffin Cells)
Central Nervous System
Gs has a stimulatory effect on Adenylyl Cyclase as a result,
it increases cAMP
Gi has inhibitory effect on Adenylyl Cyclase as a result,
it decreases cAmp
Gq activation will release Phospholipase C which will synthesize DAG and IP3 as a result,
it will facilitate the release of calcium from the Sarcoplasmic Reticulum
SR, CM, and Ca++ - CM means
Sarcoplasmic Reticulum, Calmodulin, Calcium-Calmodulin Complex
MLC, MLCK, MLCP means
Myosin Light Chain, Myosin Light Chain Kinase, Myosin Light Chain Phosphatase
cAMP and cGMP means
Cyclic Adenosine Monophosphate, Cyclic Guanosine Monophosphate
IP3, DAG, and NO means
Inositol Triphosphate, Diacylglycerol, Nitric Oxide
The Alpha 1 Gq-linked receptor in the Vascular smooth muscle will result in
Vasoconstriction
The Alpha 1 Gq-linked receptor in the Urinary bladder will result in
Urinary Retention
The Alpha 1 Gq-linked receptor in the Radial of the Iris will result in
Mydriasis
The Alpha 1 Gq-linked receptor in the Pilomotor smooth muscles will result in
Contraction
The Alpha 2 Gi-linked receptor in the CNS will result in
Inhibition of further release of Catecholamines
The Alpha 2 Gq-linked receptor in the Peripheral blood vessels will result in
Vasoconstriction
The Beta 1 Gs-linked receptor in the Heart will result in
Inotropy, Chronotropy, Dromotropy (basically, heartbeat and BP will increase)
The Beta 2 Gs-linked receptor in the Bronchioles will result in
Bronchodilation
The Beta 2 Gs-linked receptor in the Uterine muscles will result in
Uterine Relaxation
The Beta 2 Gs-linked receptor in the Blood vessels will result in
Vasodilation
The Beta 2 Gs-linked receptor in the Neuromuscular endplates will result in
Hypokalemia (lower K levels in the bloodstream)
The Beta 2 Gs-linked receptor in the Liver will result in
Glycogenolysis (breakdown of glycogen to glucose-1-phosphate and glycogen)
The Beta 3 Gs-linked receptor in the Adipose tissues will result in
Lipolysis
The Dopamine 1 Gs-linked receptor in the Renal Blood Vessels will result in
Renal Vasodilation
The Dopamine 2 Gi-linked receptor in the GIT will result in
Loss of peristalsis
The Dopamine 2 Gi-linked receptor in the CNS will result in
Modulation of motor activity, perception, and behavior
The Beta 1 Gs-linked receptor in the juxtaglomelular apparatus will result in
Release of renin
Gq will activate the release of
Phospholipase C
Phospholipase 3 will synthesize
IP3 (Inositol Triphosphate) and DAG (Diacylglycerol)
Synthesis of DAG (Diacylglycerol) & IP3 (Inositol Triphosphate) will
Release of calcium from the Sarcoplasmic Reticulum
Stimulates more than one general type of adrenergic receptor
Non-Selective Adrenoreceptor Agonist
Properties of Endogenous catecholamines
Not Orally administered
Acid Labile
Metabolized by MAO and COMT
Indications of Epinephrine
Counteracts the effects of histamine as a physiological antagonist
Used for anaphylactic shock
Indications of Norepinephrine
“Levarterenol”
First line in the management of septic shock
Indications of Dopamine
Can be used in the management of Cardiogenic shock and Septic shock
Characteristics of Non-Catecholamines
Not substrates of COMT and MAO
Effective after oral administration
Relatively longer duration of action compared to Catecholamines
Indications of Selective Alpha-1 Agonists
Nasal Congestion
Reducing regional blood flow to achieve hemostasis during surgery
Reducing diffusion in local anesthetics
Adverse effects of Selective Alpha 1-Agonists
Rhinitis medicamentosa (rebound congestion)
Urinary Retention
Exacerbation of hypertension (elevation of blood pressure)
Indications Selective Alpha-2 Agonists (CNS)
Clinically used to normalize blood pressure in patients w/ hypertension
Acts by reducing sympathetic tone in the CNS
Most common side/adverse effect of Selective Alpha-2 Agonist
Sedation
Clonidine indications include
Hypertensive Urgency
Management of ADHD
Facilitate abstinence from opioid dependence
Methyldopa FDA approved indication
Management of hypertension in pregnant women
Non-Selective Beta Agonist
Isoproterenol
“Isoprenaline”
Indications for Isoproterenol
Alternative drug used for shock states and acute heart failure
Previously used to treat bronchial Asthma
Indications of Dobutamine
First line agent in the management of cardiogenic shock (increases cardiac output and stroke volume)
Management of acute heart failure (as an inotropic agent)
