Proteins - Lecture Thirteen Flashcards
Toxins as Inhibitors of Protein Function
Drug metabolism of alcohol
Alcohol goes into your gut and the stomach tries to get rid of it by using enzymes- ADH (alcohol dehydrogenase) first to produce an aldehyde from the alcohol. An ALDH enzyme (aldehyde dehydrogenase) then turns the aldehyde into an acetic acid
Ethylene glycol
Ethylene glycol looks like ethanol so alcohol dehydrogenase enzyme picks it up, however it is very toxic
How do you treat a patient who has ethylene glycol in their system?
Add ethanol so the ADH enzymes are reacting with the ethanol instead of ethylene glycol
How do drugs act?
Drugs bind to things in cells and change stuff (to do this they often interact with cellular proteins).
Types of receptors
Form a channel across the membrane
Transmit a signal across the membrane
Membrane bound enzymes
Intracellular
Receptor
A protein molecule that receives chemical signals from outside a cell
Ligands
A molecule, or drug, that binds to a receptor (agonist and antagonist)
Agonist
A chemical capable of activating a receptor to induce a response
Antagonist
A drug that blocks the receptor and stops the effects of another drug or molecule
GABAa receptor
A membrane bound ligand gated chloride channel that has many ligands including benzodiazepines (sedatives) and barbiturates (sedative) GABAa receptors also inhibit
Alcohol and GABAa
Agonist binding opens the channel and allows chloride ions (Cl-) into the cell, this decreases the general activity in the nervous system causing loss of co-ordination, memory loss and slurred speech. The effects are dose dependant as lower doses are associated with relaxation and higher doses with coma or death