In the mathematical model (Ref. 1) two parameters may change the outcome of FT4:
k32 – positive feedforward of TSH onto FT4 (downstream, activating) and
a 3 – the FT4 elimination rate constant.
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Only examples of the effect of the parameter –
- Hoermann R, Pekker MJ, Midgley JEM, Larisch R and Dietrich JW (2022) Principles of Endocrine Regulation: Reconciling Tensions Between Robustness in Performance and Adaptation to Change. Front. Endocrinol. 13:825107. doi: 10.3389/fendo.2022.825107 https://www.frontiersin.org/articles/10.3389/fendo.2022.825107/full