30. a. Occupation theory D + R DR RESPONSE :response is proportional to the fraction of occupied receptors :maximal response occurs when all the receptors are occupied
31.
32. BIOLOGICAL STIMULUS PERCENT RECEPTOR OCCUPANCY 0% 100% BIOLOGICAL RESPONSE RECEPTOR RESERVE TRETHOLD 0% 100% Max Effect Threshold Effect Schematic representation of the relationship between threshold, receptor reserve, receptor occupancy, biological stimulus and biological response
33. Receptors are said to be spare for a given pharmacological response when the maximal response can be elicited by an agonist at a concentration that does not result in occupancy of the full complement of available receptors
34.
35.
36.
37. Affinity: measure of propensity of a drug to bind receptor; the attractiveness of drug and receptor Efficacy: Potential maximum therapeutic response that a drug can produce. Potency: A mount of drug needed to produce an effect.
38.
39.
40. Classification of Ligands a. agonist b. partial agonist c. antagonist pharmacological vs. physiological vs. chemical pharmacological antagonists - competitive surmountable - noncompetitive
45. [D] (concentration units) % Maximal Effect 0.01 0.10 1.00 10.00 100.00 1000.00 0.0 0.2 0.4 0.6 0.8 1.0 Partial agonist Full Agonist Partial agonist PARTIAL AGONISTS - EFFICACY Even though drugs may occupy the same # of receptors, the magnitude of their effects may differ.
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