EC50: Difference between revisions

    From Longevity Wiki
    No edit summary
    No edit summary
    Line 1: Line 1:
    {{Short description|Concentration of a compound where 50% of its maximal effect is observed}}
     
    {{DISPLAYTITLE:EC<sub>50</sub>}}
    {{DISPLAYTITLE:EC<sub>50</sub>}}
    [[File:Dose_response_antagonist.jpg|right|thumb|400px|The tissue response (y-axis) to an agonist, in log concentration (x-axis), in the presence of different antagonist concentrations. The EC<sub>50</sub> of the agonist is represented by the x co-ordinate that corresponds with the half-maximum of the leftmost curve. This is denoted by [A]]]
    [[File:Dose_response_antagonist.jpg|right|thumb|400px|The tissue response (y-axis) to an agonist, in log concentration (x-axis), in the presence of different antagonist concentrations. The EC<sub>50</sub> of the agonist is represented by the x co-ordinate that corresponds with the half-maximum of the leftmost curve. This is denoted by [A]]]
    '''Half maximal effective concentration''' ('''EC<sub>50</sub>''') is a measure of the concentration of a drug, antibody or toxicant which induces a [[stimulus–response model|biological response]] halfway between the baseline and maximum after a specified exposure time.<ref>{{cite web|url=http://www.graphpad.com/curvefit/introduction89.htm |title=Introducing dose response curves |archive-url=https://web.archive.org/web/20120730150339/http://www.graphpad.com/curvefit/introduction89.htm |archive-date=2012-07-30 |publisher=Graphpad Software}}</ref> More simply, EC<sub>50</sub> can be defined as the ''concentration required to obtain a 50% [...] effect''<ref>{{Cite journal |last1=Chen |first1=Zheng |last2=Bertin |first2=Riccardo |last3=Froldi |first3=Guglielmina |date=2013-05-01 |title=EC50 estimation of antioxidant activity in DPPH assay using several statistical programs |url=https://www.sciencedirect.com/science/article/pii/S0308814612016020 |journal=Food Chemistry |language=en |volume=138 |issue=1 |pages=414–420 |doi=10.1016/j.foodchem.2012.11.001 |pmid=23265506 |issn=0308-8146}}</ref> and may be also written as [A]<sub>50</sub>.<ref name = Terms>{{cite journal |title=International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification. XXXVIII. Update on Terms and Symbols in Quantitative Pharmacology|url=https://www.guidetopharmacology.org/pdfs/termsAndSymbols.pdf|last1=Neubig|first1=Richard R.|journal=Pharmacological Reviews|year=2003|volume=55|issue=4|pages=597–606|doi=10.1124/pr.55.4.4|pmid=14657418|s2cid=1729572}}</ref> It is commonly used as a measure of a drug's [[Potency (pharmacology)|potency]], although the use of EC<sub>50</sub> is preferred over that of 'potency', which has been criticised for its vagueness.<ref name = Terms/> EC<sub>50</sub> is a measure of concentration, expressed in [[Molar concentration|molar units]] (M), where 1&nbsp;M is equivalent to 1&nbsp;[[Mole (unit)|mol]]/[[Liter|L]].  
    '''Half maximal effective concentration''' ('''EC<sub>50</sub>''') is a measure of the concentration of a drug, antibody or toxicant which induces a biological response halfway between the baseline and maximum after a specified exposure time.<ref>{{cite web|url=http://www.graphpad.com/curvefit/introduction89.htm |title=Introducing dose response curves |archive-url=https://web.archive.org/web/20120730150339/http://www.graphpad.com/curvefit/introduction89.htm |archive-date=2012-07-30 |publisher=Graphpad Software}}</ref> More simply, EC<sub>50</sub> can be defined as the ''concentration required to obtain a 50% [...] effect''<ref>{{Cite journal |last1=Chen |first1=Zheng |last2=Bertin |first2=Riccardo |last3=Froldi |first3=Guglielmina |date=2013-05-01 |title=EC50 estimation of antioxidant activity in DPPH assay using several statistical programs |url=https://www.sciencedirect.com/science/article/pii/S0308814612016020 |journal=Food Chemistry |language=en |volume=138 |issue=1 |pages=414–420 |doi=10.1016/j.foodchem.2012.11.001 |pmid=23265506 |issn=0308-8146}}</ref> and may be also written as [A]<sub>50</sub>.<ref name = Terms>{{cite journal |title=International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification. XXXVIII. Update on Terms and Symbols in Quantitative Pharmacology|url=https://www.guidetopharmacology.org/pdfs/termsAndSymbols.pdf|last1=Neubig|first1=Richard R.|journal=Pharmacological Reviews|year=2003|volume=55|issue=4|pages=597–606|doi=10.1124/pr.55.4.4|pmid=14657418|s2cid=1729572}}</ref> It is commonly used as a measure of a drug's potency, although the use of EC<sub>50</sub> is preferred over that of 'potency', which has been criticised for its vagueness.<ref name = Terms/> EC<sub>50</sub> is a measure of concentration, expressed in molar units (M), where 1&nbsp;M is equivalent to 1&nbsp;mol/L.  


    The EC<sub>50</sub> of a ''graded'' [[dose response curve]] therefore represents the concentration of a compound where 50% of its maximal effect is observed.<ref>{{cite web|url=http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-E/EC50.html|title=Northwestern Molbiosci EC50 definition|access-date=2019-05-27}}</ref>  
    The EC<sub>50</sub> of a ''graded'' dose response curve therefore represents the concentration of a compound where 50% of its maximal effect is observed.<ref>{{cite web|url=http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-E/EC50.html|title=Northwestern Molbiosci EC50 definition|access-date=2019-05-27}}</ref>  
    The EC<sub>50</sub> of a ''quantal'' dose response curve represents the concentration of a compound where 50% of the population exhibit a response,<ref>{{Cite web |url=http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm%2Fbc%2F190116.htm |title=Drug Dose and Clinical Response |access-date=2019-04-16 |archive-url=https://web.archive.org/web/20070220004824/http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm%2Fbc%2F190116.htm |archive-date=2007-02-20 |url-status=dead }}</ref> after a specified exposure duration.
    The EC<sub>50</sub> of a ''quantal'' dose response curve represents the concentration of a compound where 50% of the population exhibit a response,<ref>{{Cite web |url=http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm%2Fbc%2F190116.htm |title=Drug Dose and Clinical Response |access-date=2019-04-16 |archive-url=https://web.archive.org/web/20070220004824/http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm%2Fbc%2F190116.htm |archive-date=2007-02-20 |url-status=dead }}</ref> after a specified exposure duration.


    Line 16: Line 16:


    * [[IC50|IC<sub>50</sub>]]
    * [[IC50|IC<sub>50</sub>]]
    * {{SeeWikipedia|EC50}}


    == References ==
    == References ==
    <references />
    <references />

    Revision as of 20:24, 23 December 2023


    The tissue response (y-axis) to an agonist, in log concentration (x-axis), in the presence of different antagonist concentrations. The EC50 of the agonist is represented by the x co-ordinate that corresponds with the half-maximum of the leftmost curve. This is denoted by [A]

    Half maximal effective concentration (EC50) is a measure of the concentration of a drug, antibody or toxicant which induces a biological response halfway between the baseline and maximum after a specified exposure time.[1] More simply, EC50 can be defined as the concentration required to obtain a 50% [...] effect[2] and may be also written as [A]50.[3] It is commonly used as a measure of a drug's potency, although the use of EC50 is preferred over that of 'potency', which has been criticised for its vagueness.[3] EC50 is a measure of concentration, expressed in molar units (M), where 1 M is equivalent to 1 mol/L.

    The EC50 of a graded dose response curve therefore represents the concentration of a compound where 50% of its maximal effect is observed.[4] The EC50 of a quantal dose response curve represents the concentration of a compound where 50% of the population exhibit a response,[5] after a specified exposure duration.

    For clarification, a graded dose response curve shows the graded effect of the drug (y axis) over the dose of the drug (x axis) in one or an average of subjects. A quantal dose response curve shows the percentage of subjects where a response is noted in an all-or-none manner (y axis) over the dose of the drug (x axis).

    For competition binding assays and functional antagonist assays IC50 is the most common summary measure of the dose-response curve. For agonist/stimulator assays the most common summary measure is the EC50.[6]

    The EC50 is also related to IC50 which is a measure of a compound's inhibition (50% inhibition).

    See Also

    References

    1. Introducing dose response curves, http://www.graphpad.com/curvefit/introduction89.htm
    2. Chen et al.; "EC50 estimation of antioxidant activity in DPPH assay using several statistical programs" , https://www.sciencedirect.com/science/article/pii/S0308814612016020 , https://doi.org/10.1016/j.foodchem.2012.11.001
    3. 3.0 3.1 Neubig et al.; "International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification. XXXVIII. Update on Terms and Symbols in Quantitative Pharmacology" , https://www.guidetopharmacology.org/pdfs/termsAndSymbols.pdf , https://doi.org/10.1124/pr.55.4.4
    4. Northwestern Molbiosci EC50 definition, http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-E/EC50.html
    5. Drug Dose and Clinical Response, http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm%2Fbc%2F190116.htm
    6. Cite error: Invalid <ref> tag; no text was provided for refs named Assay