Introduction to Pharmacology and Toxicology- Transporters as targets Flashcards Preview

PM2C: Therapeutics and Patient Care: Autumn > Introduction to Pharmacology and Toxicology- Transporters as targets > Flashcards

Flashcards in Introduction to Pharmacology and Toxicology- Transporters as targets Deck (21):
1

What membranes does passive diffusion require?

Doesn't require any proteins
Example: glycerol- no membrane needed to diffuse across

2

What membranes does facilitated diffusion require?

Requires a protein, substance flows along concentration gradient
Example: Glucose transporters- to and from the brain- blood brain barrier

3

What membranes does Primary Active Transport require?

Requires a protein which a substance flows against concentration gradient

This requires energy to provide directly by ATP hydrolysis- Na+K+ATPase- transfers multiple ions

4

What membranes does Secondary Active Transport require?

Requires a protein where substance flows against concentration gradient

Energy required provided indirectly by ATP hydrolysis
Gradient of ion used to couple transport (usually sodium)

Can be simper or antiport mechanism
Can go forward or backward

5

What does it mean by facilitated transport is saturated?

Can only have as much substrate on the extracellular domain, cannot transport anymore of that ion or that molecule due to the levels of substrate concentration

Need active transport to solve the issue

6

What are the different classes of pumps?

1. P class pumps
2. V class pumps
3. F class pumps
4. ABC (ATP binding cassete)

7

What is the function of the P class pump work and what does it transport?

1. Transports all types of ion- phosphorylation event occurs
2. Only specific to one or two kinds of ions
3. Transport more than one type of ion at a time
4. Example: Na+/K+ pump

8

What is the function of the V class Pump and what does it transport?

1. Only transports protons
2. Structure is very different to P class
3. They are normally used to maintain a low pH in vacuoles and Lysosomes

9

What is the function of the F class pump and what does it transport?

1. Only transports protons down its electrochemical gradient, using the movement of protons to power ATP synthesis
2. Structure is very different to F class
3. Example: ATP synthase pump found in mitochondria

10

What is the function of the ABC (ATP Binding Cassette) and what does it transport?

1. Superfamily of pumps that can transport all kinds of molecules- including polysaccharides and proteins

2. All pumps contain two transmembrane domains and two cytosolic domains which bind ATP

3. Example: CFTR pump in the membrane of epithelial cells can cause cystic fibrosis if mutated

11

What are the different 3 transporter families?

1. Ion transporters and pumps- sodium potassium ATPase

2. Metabolite transporters

3. Neurotransmitter Transporters
- vascular
- plasma membranes

12

What are the metabolite transporters and give an example?

1. Drug super family of transporters

2. Chloroquine Resistance Transporter (PfCRT) Family:
some malarial parasites have developed resistance to chloroquine through mutations in this transporter

13

What are the Neurotransmitter transporters I?

1. Vesicular inhibitory amino acid transporter

2. Vesicular excitatory amino acid transporter

3. Vesicular amine transporters

Used for scientific research for things to be packed into vesicles and released into the synaptic terminal

Packaging neurotransmitter for release

14

What are the neurotransmitter transporters II used for? And give some examples

In the plasma membrane that's tailored to specific transporters
NET- Noradrenaline transporter
DAT- dopamine transporters
5-HT Transporters
EAAT- Excitatory amino acid transporters
GAT- GABA transporters
GlyT- Glycine transporters

15

How does the pre synaptic terminal and post synaptic terminal work?

The presynaptic terminal sends a signal of serotonin containing vesicle through the serotonin transporter/5-HT transporter

16

How does the 5-HT+ transporter works?

For one K+, one Na+ and Cl- comes along

17

What does serotonin do?

Creates happy thoughts

18

What does citalopram do?

1. Blocks serotonin reuptake (member of the SSRIs)
2. More increase of serotonin signal so it stays longer
3. Indication: Depressive illness, panic disorder

19

What does the dexamfetamine do?

1. Blocks monoamine transporters (including the dopamine family)
2. Stimulant that increase the levels of central nervous system stimulate
3. Indication: narcolepsy, refractory attention deficit, hyperactivity disorder

20

What does cocaine do?

Bind to the dopamine transporter and acts as an antagonist

21

What does Riluzole do?

1. Reduces glutamate "excitotoxcity" via multiple interactions

2. One target is the EAATS where suggests an up regulation of transporter proteins

3. Indication: extend life of patients with amyotrophic lateral sclerosis
- initiated by specialists experienced in the management of motor neurone disease