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→Full and Partial Agonists
'''Please Insert Appropriate Graphs'''
'''Please Insert Appropriate Graphs'''
[[File:Dose-Response Curve.png|thumb|Add caption here]]
[[File:Dose-Response Curve.png|thumb|dose-response curve used to calculate EC50]]
From these graphs two figures can be achieved, the '''ED50''' or '''EC50'''. The ED50 is the effective dose at which 50% of a maximal response occurs or 50% of individuals respond. The EC50 is the same but is the effective concentration. Agonists with higher affinities will have a lower concentration and so EC50 than an agonist with a lower affinity. The first drug is therfore said to be more '''potent'''.
From these graphs two figures can be achieved, the '''ED50''' or '''EC50'''. The ED50 is the effective dose at which 50% of a maximal response occurs or 50% of individuals respond. The EC50 is the same but is the effective concentration. Agonists with higher affinities will have a lower concentration and so EC50 than an agonist with a lower affinity. The first drug is therfore said to be more '''potent'''.
The difference between the full and partial agonist is it's '''efficacy'''. This is defined as the strength of the tissue response that results from the formation of a agonist-receptor complex. The efficacy of the partial agonist is lower than that of the full agonist.
The difference between the full and partial agonist is its '''efficacy'''. This is defined as the strength of the tissue response that results from the formation of a agonist-receptor complex. The efficacy of the partial agonist is lower than that of the full agonist.
It is still unclear why molecules that are chemically very similar have differing efficacies. Only now are the mechanisms behind it being gradually understand. This however doesn't mean that we ignore efficacy. It is of great practical importance as some drugs of equal affinity for a specific receptor may have widely differing efficacy.
It is still unclear why molecules that are chemically very similar have differing efficacies. Only now are the mechanisms behind it being gradually understand. This however doesn't mean that we ignore efficacy. It is of great practical importance as some drugs of equal affinity for a specific receptor may have widely differing efficacy.
===Inverse Agonists===
===Inverse Agonists===