Drugs are evenly distributed around the body. True or false?
Irreversible binding is mainly confined to what?
Receptor binding sites
Ion channels
Enzyme inhibitors
Transport/carrier proteins
Irreversible binding uses what type of bonding?
Covalent
Hydrogen
Ionic
Van der Waals
Which of the following are examples of natural binding sites?
Modulatory sites
Allosteric sites
Enzyme active sites
Modulatory or allosteric sites are a type of separate site to which drugs can bind. True or false?
Drugs that block function are known as
Antagonists at receptors
Inhibitors at transporters/carriers
Blockers at ion channels
Inhibitors at enymes
What is the generic name for Adrenaline?
Fluoxetine
Noradrenaline
Epinephrine
Tetracycline
What is the generic name for Aspirin?
Mefanamic acid
Diacetylmorphine
Acetylsalicylic acid
What is the generic name for Heroin?
What is the generic name for Prozac?
The use of an antagonist on a receptor results in
Enzyme activition
Opening of ion channels
No effect produced
Blockage of endognous mediators
What direct mechanism would an agonist have on a receptor molecule?
Enzyme activation or inhibition
Opening or closing of ion channels
Modulation of ion channels
DNA transcription
What transduction mechanisms may occur due to the activity of an agonist on a receptor molecule?
Ion channel modulation
Enzyme inhibition or activation
Opening or closing of ion channel
Proteins that bind to specific molecules, called ligands, to produce a response are known as receptors. True or false?
When drugs act through receptors, these receptors will always have exogenous ligands. True or false?
Examples of endogenous ligands are
Hormones
Neurotransmitters
The endogenous ligand is always an agonist. True or false?
In the absence of ligands, receptors have no other function. True or false?
Where are most receptors found?
Embedded in the plasma membrane
Circulating in the blood
Lining the epithelium of the gut
In the brain
Which of the following statements are true regarding antagonists?
They bind loosely to receptors
The produce no effect themselves
They prevent agonists from binding
The block the response
Which of the following statements is false regarding Histamine?
It is an endogenous agonist
Binds to receptors on stomach parietal cells
Is an exogenous agonist
Causes release of gastric acid
Which of the following blocks the parietal histamine receptors?
Acetylcholine
Ranitidine
Histamine receptor H1 mediates which effect on the gastrointestinal tract?
Inflammation
Bile secretion
Smooth muscle contraction
Gastric acid secretion
Histamine receptor H2 mediates which effect on the gastrointestinal tract?
Secretion of gastric acid
Which anatagonist acts upon Histamine receptor H2 to prevent secretion of gastric acid?
Mepyramine
Which antagonist acts upon Histamine receptor H1 to prevent contraction of smooth muscle in parietal cells?
Different receptors for the same endogenous agonist are called subtypes. True or false?
Which of the following are a type of receptor family?
Ionotropic receptors (ligand-gated ion channels)
Kinase-linked receptors
Nuclear receptor (cytoplasmic)
Metabotropic receptors (G-protein coupled receptors)
Which of the following statements are true concerning ionotropic receptors?
Channel formed from 3-5 subunits
Pore domain of each subunit forms a hydrophobic channel
Ligands bind to an intracellular domain
Ions flow selectively through the membrane
The following is typical of the mechanism of receptors incorporating ion channels: 1. Agonist binds to receptor 2. Change in ion concentration in the cell 3. Depolarisation or hyperpolarisation occurs 4. Cellular effects (response)
Nicotinic acetylcholine receptor is a part of the ionotrophic receptor family. True or false?
Which of the following statements is false regarding Metabotropic receptors? (G-protein coupled receptors)
Consists of a single polypeptide
7 transmembrane domains
Domains consist of beta helices
Ligand binds either to extracellular domain or within transmembrane domain
Muscarinic acetylcholine receptors are in the family of metabotropic receptors. True or false?
Alpha and beta adrenoceptors are examples of the 2nd messenger effects of GCPRs. True or false?
