F3 Biological factors

How does species play a role in biological factors

They have different international system, those closest to us are therefore most ideal for drug testing

Which route of absorption does hypdrophillic drugs typically take if administrered on the skin

They take the intercellular route (between cells) as they cant easily cross the cell lipid layers

Which route of absorption does hydrophobic drugs typically take if administrered on the skin

They take the transcellular route as they easily can cross the lipid layers of the cell membrane

Why were canaries used as gas indicators in mines?

Because they have a higher metabolisme rate than humans, and would therefore more quickly react to dangerouse gasses (large capacity in blood, uptake before equilibrium and so on)

Phase 1 oxidation differences in animals

It differs as there are different preferred oxidative pathways, cats exccretes at much higher rates than rabbits

Phase 1 hydrolysis difference in animals

Insects metabolises differently, that is how insecticides function for example

What are strain differences

It is genetic differences

Why are some chemicals more carcinogenic in male rats

They have a greater biliary secretion of glucuronide conjugates which are reabsorbed by enterohepatic circulation

What is enterohepatic circulation

Movement of bile acid molecules from small intestines back to the liver

Which enzyme is important in alcohol metabolism

AHD and ALDH

Defiencies of ALDH2

Less functional ALDH therefore lower metabolisme (asian flush)

Lack in nutrients effect on metabolism

Can cause depression of metabolic activity

Protein deficiency effect on metabolism

Loss of enzyme activity, low activity and conc. of P450, low liver microsomal proteins

Consequences of protein deficient diet

Can cause some drugs to become more hepatotoxic (liver damage) or even some less hepatotoxic

Protein deficiency and paracetamol

Causes it to not properly be metabolised and therefore increased hepatotoxicity

Extreme ages (infant or very old) and metabolism

Impairment of drug metabolism, altered plasma-binding capacity is altered and clearance of forreign substances is reduced

Consequences of age and metabolisme in active drugs without metabolisation

They can especially cause problems in older people and infants as it will achieve a prolonged and exaggerated response (can cause death)

Consequences of age and prodrugs

Paracetamol becomes less hepatotoxic due to low P450 and GSH levels