Transporters as drug targets

Question 1

Why use transporters as drug targets?

Answer 1

• correct spatial disposition of signalling molecule important for their function
• neurotransmitters released into synaptic cleft to function
• regulate position of signalling molecules

Question 2

What is the structure of a nephron?

Answer 2

• filtration of plasma allows water to pass into kidney tubule w/ small molecules
• sodium pumped from tubule into interstitial tissue
• water follows sodium due to osmotic pressure
• results in water being reabsorbed
• inhibiting sodium pumps with diuretics inhibiting water being reabsorbed
• promotes diuresis
• diff drugs inhibits sodium pumps

Question 3

What is Heart failure?

Answer 3

• inadequate CO
• treatments must increase CO
• increase power of each cardiac muscle contraction
• digoxin acts of Na+K+ATPase

Question 4

What is the digoxin effect in cardiac recovery?

Answer 4

• excitation of cardiac tissue causes calcium influx
• release of calcium from intracellular stores
• calcium promotes myofibril contraction
• calcium expelled/returned to sarcoplasmic reticulum
• calcium expulsion coupled to sodium influx
• sodium reflex coupled to potassium influx by antiporter
• digoxin inhibits sodium- potassium antiporter
• elevated intracellular sodium reduces gradient driving calcium reflex
• slow efflux allows time for calcium to be pumped back
• increases amount of calcium available for next contraction
• thus creates a greater contractile force generated

Question 5

How does antidepressant medication work?

Answer 5

• SSRIs have selective serotonin reuptake inhibitors preventing serotonin reuptake from the serotonin reuptake from synaptic cleft
• SNRIs reuptake inhibitors prevent reuptake of serotonin and noradrenaline
• tricyclic antidepressants inhibit serotonin and noradrenalin reuptake

Question 6

What is exetimibe?

Answer 6

• inhibits absorption of cholesterol across intestinal brush border
• reduces elevated cholesterol

Question 7

How do transporters inhibit drug action?

Answer 7

• transporter as drug efflux pumps
• prevent drug from reaching targets
• transporter not drug target, modifying response to drug

Question 8

How do transporter facilitate drug action?

Answer 8

• transporter acts as drug pump
• assist drug in reaching target
• loop diuretic pumped into lumen of tubule
• facilitates loop diuretic reach NKCC2

Question 9

How do transporters act as drug targets?

Answer 9

• passive transport
• Active Transport
• Coupled transporter