Mathematical representation of some endocrinological systems

An integrative mathematical approach to endocrinological homeostasis is presented. By means of it, three homeostatic systems of increasing complexity are analyzed. The two-variable system described embraces the thyroid hormone and the thyrotropic hormone; the three-variable system, calcium, phosphate, and the parathyroid hormone; and the fourvariable system, sodium, water, the antidiuretic hormone, and aldosterone. The Laplace transforms of the variables are found. The handling of these transforms utilizes well-known techniques.