Long Slide Part 2 Flashcards
Binding of drugs in —— binding domain induces —— changes, alter distribution of charges and transmitted to —— domain to be transmitted to —— domain
Ligand
Confirmational
Coupling
Effector
Binding can be specific and irreversible. T/F
False it’s reversible
Binding or interaction of drug-receptor is by what means?
Chemical bonds
Ligands bind to?
Receptors
Individual receptors have the same amino acid sequencing. T/F
False. They are different
Examples of Acetylcholine
Muscarinic and Nicotinic
Examples of Muscarininc receptor subtypes
M1, M2, M3, M4, M5
Examples of Nictotinic receptor subtypes
Nm and Nn
What is the oldest and classical criteria of classification of receptors based on potencies of selective agonist and agonists. Give examples
Muscarinic
Nicotinic
Alpha and Beta adrenergic
Measurement of specific binding of high affinity radio labeled ligand to cellular fragments usually membranes in vitro and it’s selective displacement by various selective agonist/antagonists is used to delineate receptor subtype. This Criteria of classification is under?
Give me examples
Ligand binding
Multiple 5-HT receptors were distinguished by this approach
In what receptor criteria is a receptor subtypes distinguished by the mechanism through which their activation is linked to the response?
Give examples
Transducer pathway
M cholinergic receptors act through G-proteins
N cholinergic receptor gates influx of sodium ions
The cardiac receptor is beta adrenergic receptor as beta 2. T/F
False it’s Beta 1
The bronchial adrenergic receptor is Beta 2. T/F
True
Receptors without known ligands are called?
Orphan receptors
The receptor protein is cloned and it’s amino acid sequence as well as three dimensional structure is worked out. What type of Receptor Criteria is this?
Molecular cloning
What Receptor Criteria approach led to flood of receptor subtypes and several isoforms?
Molecular cloning
Receptors are regulatory binding sites capable of ———
Generating a response
What kind of receptors bind drugs to them with no pharmacological response?
Silent receptors
What type of receptors are called drug acceptors or sites of loss?
Plasma proteins
Silent receptors are also called?
Drug acceptors or Sites of loss
What Receptor Criteria can you find receptors without known ligands?
Molecular cloning
What kind of receptor can produce maximal response when even less than 1% of the receptor is occupied?
Spare receptors
Depletion of noradrenaline/treatment with adrenergic antagonists results in?
Super-sensitivity of tissues to noradrenaline and your increase in receptor number
Administration of beta blocker causes a decrease in adrenergic receptors. T/F?
False. It causes an increase
What is up regulation?
Increase in number of receptors and subsequent increase in receptor sensitivity
What is reduction in number of receptors available for activation known as?
Down regualtion
Continued exposure to drugs/agonist can result in?
Desensitization, tolerance, refractoriness
Down regulation of receptors leads to?
Decreased No of receptors
Reduced affinity to drug
Repeated administration of Adrenergic agonist in asthma leads to down regulation of beta receptors. T/F
True
I’m Myasthenia Gracias autoantibodies inactivate what?
Nicotinic acetylcholine receptors
Autoantibodies can also mimic the effects of antagonists. T/F
False. Agonist
What an example of a case where autoantibodies mimic the effects of agonist?
Thyroid hyper-secretion caused by activation of thyrotropin receptors
Mention the receptor related diseases
Testicular feminisation
Insulin resistant diabetes
Familial hypercholesterolaemia
Most transmembrane signaling is accomplished by a large number of different molecular mechanisms. T/F
False! It’s small
What are the four major categories of transducer mechanism?
GPCR
Receptors with intrinsic ion channel
Enzyme linked receptors
Transcription factors(receptors for gene expression)
What receptors mediate the majority of cellular responses to external stimuli?
GPCR
Ligand binding and channel opening occur on a millisecond timescale so they are confirmed to excitable tissues. What are those excitable tissues?
CNS
NMJ
Autonomic ganglia
Receptors mediate diverse functions such as?
NT
Cardiac conduction
Muscle contraction
Stimulation of Nicotinic receptor by Ach results in ———
Na influx
Generation of AP
Activation of skeletal muscle contraction
What enhances the stimulation of GABA, resulting in increased Chloride influx and hyper-polarization of the respective cell?
Benzodiazepines
