Bulletin of Mathematical Biology

, Volume 68, Issue 6, pp 1383–1399 | Cite as

A Stochastic Model of Oscillatory Blood Testosterone Levels

Original Article

Abstract

A continuous-time, discrete-state stochastic model of testosterone secretion in men is considered. Blood levels of testosterone in men fluctuate periodically with a period of 2–3 h. The deterministic model, on which the stochastic model considered here is based, is well studied and has been shown to have a globally stable fixed point. Thus, no sustained oscillations are possible in the deterministic case. However, the stochastic model does observe periodic, pulsatile behavior. This demonstrates how oscillations can occur due to a switching behavior dependent on the random degradation of testosterone molecules in the system. The Gillespie algorithm is used to simulate the hormone secretion model. Important parameters of the model are discussed and results from the model are compared to experimental observations.

Keywords

Testosterone Endocrine system Hormones Stochastic hormone model Negative feedback 

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Copyright information

© Society for Mathematical Biology 2006

Authors and Affiliations

  1. 1.Department of Applied MathematicsUniversity of WashingtonSeattleUSA

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