Term: second messenger
https://doi.org/10.1351/goldbook.ST06842

Definition:
Intracellular effector substance increasing or decreasing as a response to the stimulation of a receptor by an agonist, considered as the 'first messenger'.

Related Terms:
1) effector (http://doi.org/10.1351/goldbook.E01901).
2) agonist (http://doi.org/10.1351/goldbook.A00186).
3) receptor (http://doi.org/10.1351/goldbook.RT06841).

Source: PAC, 2004, 76, 1033. 'Glossary of terms used in toxicokinetics (IUPAC Recommendations 2003)' on page 1070 (https://doi.org/10.1351/pac200476051033)

Citation: 'second messenger' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.ST06842

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