Computer simulation tools for education and research are making increasingly effective use of the internet. To facilitate these activities in neuroendocrinology, we implemented a sophisticated and well-validated simulator of the dynamics of human thyroid hormone and thyrotropin regulation as a web-based application. A major goal was to accommodate access to this tool from virtually anywhere, on modern handheld devices as well as desktop computers and laptops. Development was done using well-established open source software components that together provide a simple and intuitive user interface platform for doing simulated "what-if" experiments. User-selectable "experimental" test-input stimuli (oral, IV-pulse, IV-infusion inputs) are represented by animated graphical icons. Familiar graphs of simulated time-dependent T3, T4 and TSH dynamic responses are provided on the same interface. Various disease states, e.g. hypo- and hyperthyroidism and malabsorption, are simulated by optionally changing thyroid gland secretion rates and gut absorption rates. To facilitate comparative analysis, two sets of simulated experimental results can be superimposed on the same graph.
