Aromatase inhibitors are the compounds that serve to reduce estradiol levels in blood by eliminating the production of estradiol through binding to and disabling the aromatase enzyme, which is responsible for the conversion (or aromatization) of androgens into estradiol. Suicidal aromatase inhibitors serve to permanently inhibit and disable the aromatase enzyme to which it is bound to. This renders the enzyme inactive forever. The body will eventually manufacture more aromatase enzymes, but the currently-bound enzymes are bound indefinitely, eliminating any risk for estrogen rebound. This is the main difference compared alongside two other major aromatase inhibitors: anastrozole and letrozole, which are non-suicidal aromatase inhibitors that are only bound to the aromatase enzyme for limited time periods. If a non-suicidal aromatase inhibitor is halted too abruptly, the circulating inhibited aromatase enzymes that have not been metabolized out of the body will then become free again, and begin aromatizing androgens into estrogens at an often rapid rate. This is not the case with Exos.
Much of the art in this book consists of black line illustrations. The strongest line is used to highlight the most important structures, and shading is used to show dimension and shape. Color is used sparingly to highlight and clarify the primary anatomical or functional point of the illustration. This technique is intended to draw students’ attention to the critical learning point in the illustration, without distraction from excessive gradients, shadows, and highlights. Full color is used when the structure or process requires it (for example, muscle diagrams and cardiovascular system illustrations).