A new theoretical description of the binding of thyroid hormones by serum proteins.

A theoretical model is proposed which describes the binding of thyroid hormones to serum proteins in terms of easily determined parameters, Not only free hormone concentration but also the distribution of hormone among various binding sites may be computed. The mathematical approach is capable of dealing with models of differing complexity of binding from simple 'one binding site per protein molecule' systems to those involving 'negative co-operativity'. The approach gives predictions of thyroid function parameters which are in good agreement with those observed in practice.