Homeostatic control of thyroxin concentration expressed by a set of linear differential equations

  • Kenneth H. Norwich
  • Raymond Reiter


The purpose of this work is to express current concepts on the relationship between the rates of secretion of thyroxin and of thyroid stimulating hormone (TSH) by a set of linear differential equations (two attempts have been made previously in this direction; cf. Roston,Bull. Math. Biophysics,21, 271–282, 1959; Danziger and Elmergreen,Bull. Math. Biophysics,16, 15–21, 1954), and to show that the solutions to these equations fulfill two criteria: that they correctly express the previously observed behavior of thyroxin and TSH, and that they allow certain predictions to be made which are amenable to experimental verification or disproval by currently existing techniques. This mathematical model is necessarily only an approximation of reality.


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Copyright information

© N. Rashevsky 1965

Authors and Affiliations

  • Kenneth H. Norwich
    • 1
  • Raymond Reiter
    • 1
  1. 1.University of TorontoTorontoCanada

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