#separator:Tab
#html:false
#tags column:5
IMF-097-01-0001-en	Why need plasma concentration, receptor occupancy, and measured effect not change in parallel?	Each link from free concentration at the site of action, through target engagement and signal transduction, to cellular, organ, and whole-person responses can amplify, buffer, delay, or oppose the one before it.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0002-en	Why does doubling ligand concentration usually fail to double receptor occupancy?	Fractional occupancy equals concentration divided by concentration plus KD, a rectangular hyperbola that approaches full occupancy asymptotically, so it is near-proportional only at very low concentrations.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0003-en	How can two ligands with the same KD differ in how long they engage their target?	Equilibrium affinity hides association and dissociation rates; residence time is roughly the reciprocal of the dissociation rate, so a slowly dissociating ligand can sustain engagement after free concentration falls.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0004-en	What distinguishes affinity from efficacy, and why can a partial agonist not reach the maximal response even at high occupancy?	Affinity describes binding, whereas efficacy is the capacity of a bound ligand to generate a response; a partial agonist contributes less activation per occupied receptor, so it cannot reach the system's maximum.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0005-en	Why can a partial agonist reduce the response when a full agonist is present?	It occupies receptors while contributing less activation than the full agonist would, so the same molecule can appear agonistic or antagonistic depending on context.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0006-en	What distinguishes an inverse agonist from a neutral antagonist, and when does the difference become observable?	An inverse agonist stabilises inactive conformations and reduces constitutive activity, while a neutral antagonist blocks agonist binding without changing basal activity; they differ visibly only when constitutive signalling is appreciable.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0007-en	Why must biased agonism be measured against an explicit reference ligand and assay?	Bias means a ligand favours one active conformation and activates downstream pathways in different proportions, but signal amplification can mimic such selectivity.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0008-en	Why is EC50 a measure of potency rather than necessarily an affinity constant?	It is the concentration producing half the observed maximum in the measured system, and it depends on affinity, efficacy, receptor abundance, coupling, tissue access, competing ligands, and the chosen endpoint.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0009-en	Why does higher potency not make a drug better?	Higher potency only means less concentration is needed for a specified effect; it does not make the drug inherently more efficacious, safer, or clinically superior.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0010-en	How do spare receptors allow EC50 to be lower than KD?	Signal amplification lets a small fraction of receptors recruit enough downstream machinery for full effect, so maximal response occurs before all receptors are occupied.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0011-en	How does progressive irreversible receptor inactivation change the curve in a tissue with receptor reserve?	While reserve is consumed the curve shifts rightward with unchanged Emax; once it is exhausted the maximum falls. Reserve varies among tissues, so one agonist can be full in one organ and partial in another.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0012-en	How does a competitive antagonist change the agonist concentration-response curve, and why?	It binds reversibly at the agonist recognition site without activating it, so more agonist can surmount it, giving a parallel rightward shift with unchanged maximum in an ideal system.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0013-en	Why does noncompetitive antagonism usually lower the maximum response, and why may this be hidden at first?	Irreversible orthosteric binding, allosteric binding, downstream transducer block, or channel block cannot be overcome by more agonist, but spare receptors can initially conceal the fall in maximum.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0014-en	Why can a functional outcome alone not reveal the mechanism of antagonism?	Opposition can also be physiological, from drugs at different targets producing opposing functions such as bronchodilation against mediator-induced constriction, or chemical, through direct interaction or sequestration.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0015-en	How can two interventions produce a supra-additive effect in the organism without synergy at their targets?	Acting at different control points, the two interventions can jointly cross a physiological threshold.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0016-en	How does an ED50 from recording whether each individual reaches an outcome differ from a graded EC50?	The ED50 is the dose effective in half the tested population for that endpoint, describing a population distribution, whereas a graded EC50 is measured within a single preparation.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0017-en	Why is a therapeutic index such as TD50 divided by ED50 only a crude guide to safety?	It crudely separates two population distributions but does not describe their tails, the severity of the endpoints, monitoring, or patient heterogeneity.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0018-en	Why can a single simultaneous blood sample misrepresent the exposure causing an effect?	Effect can lag behind or outlast plasma concentration (hysteresis) because of effect-compartment distribution, slow receptor kinetics, active metabolites, delayed transcription, irreversible binding, or feedback.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0019-en	How do desensitisation and downregulation differ in mechanism and timescale?	Desensitisation develops over seconds to hours through receptor phosphorylation, uncoupling, internalisation, mediator depletion, or channel-state change, while downregulation reduces receptor abundance over longer periods.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0020-en	Why can abruptly stopping a drug differ from simply never having been treated?	Compensatory adaptations that developed during exposure persist after the agonist or antagonist is removed, producing withdrawal or rebound.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0021-en	How can chronic antagonism or denervation produce supersensitivity?	Chronic antagonism may increase receptor number or coupling, and denervation reduces transmitter exposure, which can increase postsynaptic responsiveness.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0022-en	Why do repeated wells from one preparation not show that a concentration-response result generalises?	Repeated wells mostly estimate technical variation; estimating generalisability requires replication across independent biological preparations.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0023-en	Why should a steep Hill coefficient not be read as the number of binding sites?	A steep slope can arise from cooperativity, amplification, heterogeneity, thresholds, or assay compression.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending
IMF-097-01-0024-en	Why can potent target engagement in a simplified assay fail to yield a useful therapy?	Relevant cells may be inaccessible, redundant pathways may compensate, the same target in another tissue may cause harm, and selectivity at low exposure can be lost at higher exposure.	Integrated Medical Foundations; chapter 97, TTS module 1; https://theisegoria.github.io/medical-textbook/integrated-medical-foundations-expanded-english.md; module SHA256 at export: 09948eb4a680931feaeeb13e80cd863ce2e4ea691c7dd897669c6a8f233f25a4; editorial review pending	imf lang::en chapter::097 module::097-01 review::pending