[MEDORG-SEMIS-03-PT2] ADRENERGIC

THIS FLASHCARDS IS ABOUT [MEDORG] ADRENERGIC.

Indirect Sympathomimetics

These drugs do not bind adrenergic receptors directly. Instead they increase norepinephrine levels.

• Ephedrine

• Cocaine

What are the (2) Examples of Indirect Sympathomimetics?

Hint: EP-CO

1. Norepinephrine

2. Norepinephrine reuptake

3. Metabolism

Indirect sympathomimetics work by:

• Releasing stored (1)_____

• Inhibiting (2)_________

• Blocking (3)________

Ephedrine

This drug stimulates receptors directly and releases norepinephrine.

1. Catechol ring

2. COMT metabolism

3. Active orally

Medicinal Chemistry Characteristics of Ephedrine:

1. Lacks what ring?

2. Resistant to what metabolism?

3. Active in what way?

(This explains its longer duration)

Cocaine

This drug blocks norepinephrine reuptake transporter.

1. Tropane ring system

2. Lipophilic

Medicinal Chemistry Features of Cocaine:

1. What is the ring system of cocaine?

2. Cocaine has strong CNS effects due to what characteristic?

Selective Agonists

Adrenergic Agonists are also known as?

Adrenergic Agonists (Selective Agonists)

This group contains drug designed to activate specific adrenergic receptor subtypes.

• Phenylephrine

• Midodrine

• Clonidine

• Isoproterenol

• Albuterol

• Terbutaline

• Methyldopa

What are the (7) Adrenergic Agonists (Selective)?

Hint: PM CIA ToMorrow

Phenyleprine

This adrenergic agonist is selective a1 agonist.

1. Phenolic OH

2. Meta-hydroxyl substitution

Structure Differences from Catecholamines of Phenylephrine:

• Only one (1)________

• (2)__________ substitution

1. COMT metabolism

2. Longer duration

Effect of Phenylephrine:

1. Resistant to what metabolism?

2. What is its duration?

Nasal decongestant

Phenylephrine is used as?

Midodrine

This adrenergic agonist is a prodrug converted to desglymidodrine and acts on a1 receptors causing vasoconstriction.

1. Desglymidodrine

2. a1 receptors

3. Vasoconstriction

Midodrine is a prodrug converted to (1)________ and acts on (2)____ receptors causing (3)_________.

Orthostatic hypotension

Midodrine is used as?

Clonidine

This adrenergic agonist is selective a2 agonist.

1. Imidazoline structure

2. Lipophilic

Medicinal Chemistry of Clonidine:

1. What is the structure of clonidine?

2. This characteristic of clonidine causes CNS penetration.

Sympathetic outflow

The effect of clonidine is that it reduces ___________.

Hypertension

Clonidine is used as?

Isoproterenol

This adrenergic agonist is a synthetic catecholamine; its structure is a bulky isopropyl substituent.

Bulky isopropyl substituent

What is the structure of isoproterenol?

Strong B1 and B2 agonist

What is the effect of isoproterenol?

• Bronchodilation

• Cardiac Stimulation

Isoproterenol is used as (2)?

Hint: BRO-CAR

Albuterol

This adrenergic agonist is selective B2 agonist.

1. Non-catechol ring

2. Tert-butyl group

Medicinal Chemistry Design of Albuterol:

1. What is its ring?

2. What is its group?

Terbutalin

This adrenergic agonist is selective B2 selective agonist.

1. Bulky N-substituent

2. Non-catechol ring

Structural Features of Terbutaline:

1. What is its substituent?

2. What is its ring?

• Asthma

• Bronchospams

Terbutaline is used for (2)?

Hint: AS-BRO

Methyldopa

This adrenergic agonist is a prodrug converted to a-methylnorepinephrine.

a-methylnorepinephrine

Methyldopa is a prodrug converted to?

Central a2 receptors

Methyldopa acts on what receptors?

MAO metabolism

Medicinal Chemistry Rationale of Methyldopa:

Methyl substitution prevents the metabolism of?

Hypertension in pregnancy

Methyldopa is used as?

Adrenergic Antagonists

These drugs block adrenergic receptors.

• Phenoxybenzamine

• Tamsulosin

What are the (2) Alpha Blockers (Adrenergic Antagonists)?

Phenoxybenzamine

This alpha blocker is an irreversible a-blocker.

1. Haloalkylamine group

2. Covalent bond

Medicinal Chemistry of Phenoxybenzamine:

1. What is its group?

2. What bond does it form?

Pheochromocytoma

Phenoxybenzamine is used for?

Tamsulosin

This alpha blocker is a selective a1A blocker.

Benign prostatic hyperplasia

Tamsulosin is used for?

Receptor selectivity

Medicinal Chemistry of Tamsulosin:

Bulky aromatic groups improve?

1. Propranolol

2. Metoprolol

What are the (2) Beta Blockers (Adrenergic Antagonists)?

Hint: PRO-MET

Propranolol

This beta blocker is a prototype nonselective B-blocker.

Aryloxypropanolamine core

What is the structure of propranolol?

1. Aromatic ring

2. Secondary amine

3. Ether linkage

Medicinal Chemistry Features of Propranolol:

1. What is its ring?

2. What is its amine?

3. What is its linkage?

Metoprolol

This beta blocker is a selective B1 blocker.

B2 interaction

Structural changes in metoprolol reduces?

• Hypertension

• Heart disease

Metoprolol is used for (2)?

Hint: HY-HE