Lexicon · NucLex for innovators
Compartment model
Fully specified name: Compartment model (concept)
A model representing a system as compartments with transfers or transformations between them.
- Scope note
- Compartments need not correspond directly to anatomical spaces.
- Synonyms
- None recorded as true synonyms in this context.
- Monograph
- Biodistribution and pharmacokinetics (planned; brief only)
- External mappings
- None recorded. In W0 no mapping to SNOMED CT® or any external authority is asserted for this entry. A future mapping record will carry source system, identifier, version, relation type, evidence, author, confidence where meaningful, and review state.
- Formal status
- Editorial entry only. It is not part of any released ontology and a prose edit here changes no formal definition.
Draft. This entry is an unreviewed draft. Its sources have not been checked by a named person and no domain reviewer has approved it. Treat every claim as provisional.
Notes
A compartment model describes a system as a few pools, each holding some amount of a substance, with rates of transfer between pools and sometimes transformation within them. The amounts change over time according to those rates, usually written as differential equations. The approach is the workhorse of pharmacokinetics and internal dosimetry, where compartments might stand for blood, a tumor, the kidneys, and the rest of the body.
The word "compartment" invites misunderstanding. A compartment is a mathematical construct: a pool of substance that behaves as if well mixed and exchanges with other pools at defined rates. It may coincide with an organ, but need not. One organ may require two compartments if the substance is both free and bound there; several tissues may be lumped into one if the data cannot separate them. The number of compartments is chosen to fit the measurements, not read off the anatomy, and the same data often fit more than one structure.
Physiologists and pharmacometricians use the term in this abstract sense. Clinicians sometimes hear it as anatomical; dosimetry physicists say "source region" and "target region" for anatomical counterparts. The Systems Biology Markup Language (SBML) is a standard way to write such models for exchange between software. For NucLex a compartment model is a record of named compartments, transfer parameters with units and uncertainty, the data fitted, and the assumptions connecting compartments to biology.
Related entries
Sources consulted (1)
- SBML. What is SBML. https://sbml.org/documents/what-is-sbml/