PHARMCOLOGY

Question 1

WHAT IS PHARMACOLOGY

Answer 1

Pharmacology is a branch of medicine, biology and pharmaceutical sciences concerned with drug or medication action, where a drug may be defined as any artificial, natural, or endogenous molecule which exerts a biochemical or physiological effect on the cell, tissue, organ, or organism.

Question 2

Difference between Agonist affinity of alpha and beta

Answer 2

Adrenaline> Norepinephine> Isoprenaline

For the catecholamines the alpha is at the highest affinity for Adrenali

Activates PLC, which acts on Phosphatidylinositol
IP3/DAG as second messager

Question 3

What is the second messager for alpha receptors

Answer 3

IP3/DAG as second messenger
Antagonist: Phenoxybenzamine

Inositol triphosphate3
Diacylglycerol

Question 4

What is the Beta receptors

Agonist Highest affinity
Isoprenaline

Answer 4

isoprenaline > adrenaline > noradrenaline

2.

1. affinity atht alpha receptor is Isoprenaline

Isoprenaline is a catecholamine and at the alpha receptor the affinity
1. But it is exogenous, synthetic man made

Question 5

1. What is the second messager for beta receptors
2. Protype for the beta receptors

Answer 5

2. Antagonist: Propranolol
3. Activates: Catalyze Adeny cyclase( 2nd messager and substrate of ATP), (release by G proteins> activation which is the beta receptor (meet with the agonist, uncoupling> transduction occurs adenyl cyclase is release> ATP acted upon cAMP released as the 2 messager

Blocks both the beta 1 and 2 receptors

Question 6

What is Endogenous Catecholamines

Sympathomimetic Agents

Answer 6

1)Norepinephrine
2)Epinephrine
3)Dopamine
4)Isoprenaline ( synthetic- exogenous)

Sympathomimetic agents

Question 6

What is Endogenous Exogenous Catecholamines

Sympathomimetic Agents

Answer 6

1-3 are Endogenous Catecholamines
1)Norepinephrine
2)Epinephrine
3)Dopamine
4)Isoprenaline ( synthetic- Exogenous Catecholamines

Sympathomimetic agents

Question 7

What are Direct Acting Sympathomimetic Agents

Administer/ Action

1. Directly goes and couple the receptor.
2. Manifests sympathomimetic ActivitesIntrinsic
   Meaning/action
   sympathomimetic activity (ISA) characterizes a group of beta blockers that are able to stimulate beta-adrenergic receptors (agonist effect) and to oppose the stimulating effects of catecholamines (antagonist effect) in a competitive way.

Answer 7

1. Midodrine- a prodrug (something taken in the body and metabolized to an active metabolite) selective α1 Agonist used esp in orthostatic hypotension.
2. Phenylephrine selective α1 Agonist( remove basal constriction by vasoconstriction-block nose) for decongestion,, mydriasis and BP rise. Active orally, Not metabolized by COMT. eg Panadol, found in new tablets because its not metabolyzed by COMT-catechol-O-methyltransferase.
3. -Oxymetazoline- ( superior and improved than Phenylephrine) direct α agonist- topical decongestant
   4.Used for nasal decongestion- lng duration from each dose
   ( and acts for 12hrs asked a pharmacy for an oxyvin- ans what does it contains????)

Midodrine- flag from the FDA since it can cause high blood pressure. Used to treat patients with orthostatic hypertension then other means of treatment.
Ortho(position-reflexies is good)static hypertension- is a form of low blood pressure that happens when standing after sitting or lying down( basal position bp tends to be low but when u stand up the blood is drawn from the gravitational law, blood is pulled by the extremities and blood isn’t going to the heart or brain and BP drops) . Orthostatic hypotension can cause dizziness or lightheadedness and possibly fainting.
What is a prodrug?
Prodrugs are medications that turn into an active form once they enter the body. Prodrugs help improve a medication’s effectiveness. They may also be designed to avoid certain side effects or toxicities. Prodrugs are important for developing new medications. Certain medications only work because they’re a prodrug.

2)Example of a prodrug?
A prodrug is a medication that the body converts into a pharmacologically active drug after it is administered. Take, for example, Plavix, which is used to prevent heart attacks (and other cardiovascular events). It is inactive when absorbed, but our metabolism has an enzyme that activates it.

Question 8

What are α2 SELECTIVE AGONISTS

CALLED SELECTIVE BECAUSE THEY ACT ON SELECTIVELY ON ALPHA 1&2

Answer 8

1) CLONIDINE
2) Methyldopa
3) Guanabenz
4) Guanfacine

1) CLONIDINE- EMEARGENCY OF HYPERTENSION TREATMENT
2) Major side-effect –drowsiness/sedationindication – hypertension
3) THEY TEND TO ACT ALPHA 2 RECEPTORS AND MODULATE THE RECEPTORS OF NE AT THE SYNAPSE AND THEREFORE THEY ARE POSITIONED FOR THE TREATMENT OF HYPERTENSION. SINCE THEY ARE ACT CENTRALLY ALPHA 2 RECEPTORS UPSTARIS COMMON EFFECTS DROWINESS AND SEDATION.

Question 9

What are Beta Receptors

Answer 9

Isoproterenenol- potent nonselective agonist- ACT ON BETA 1&2.
Potent vasodilator
Selective agonist:DOBUTAMINE, Beta 2 selective
short acting- SALBUTAMOL, TERBUTALINE
long acting- SALMETEROL, FORMOTEROL

Isoproterenenol- potent nonselective agonist- ACT ON BETA 1&2.( BETA 1-INCREASES HEART RATE AND CARDIAC OUTPUT
BETA 2- IT WILL CAUSE VASODILATION AND DECREASE BP AND ATRIAL PRESSURE )
SELECTIVE AGONIST:
DOBUTAMINE- SYNTHETIC BETA 1 AGONIST
ONLY ACTING ON CARDIAC BETA 1 RECEPTORS