John A. Thomas – författare

The authors have provided an overview of the relationships between hormones that are physiologic constituents of the body as well as their pharmacologic use in replacement therapies and related endocrine dys­ function. Principles of Endocrine Pharmacology concerns itself with the ther­ apeutic use of hormones, and hormone like substances, or drugs that can act either by suppressing or enhancing the metabolism of certain glands of internal secretion. Other drugs used for nonendocrine ther­ apies can likewise affect the endocrine system. Endocrine pharmacology emerged in the early 1900s with the use of crude pituitary extracts. By the mid-1900s several investigators had isolated and begun to synthesize hormones or hormonelike substances. Recognizing the limited supply of hormones that could be obtained both from animal sources and human autopsy material, the search for so­ called hormone substitutes also began early in the 1900s. Recently, re­ combinant DNA technologies have been used to provide alternative therapeutic sources of human insulin and human growth hormone. Aside from insulin, perhaps no other use of hormonally-active sub­ stance is better exemplified by those drugs which affect fertility. The synthesis of an orally-effective steroid represented one of the first major breakthroughs in the chemical suppression of ovulation. Since the orally­ active 19-norsteroids were introduced in the 1950s, several oral contra­ ceptive steroid preparations have been marketed. Indeed, the advent of oral contraceptives for birth control has led to a renewed interest in endocrine pharmacology.

The use of performance-enhancing substances by athletes is not a contemporary epi­ demic. In fact, athletes purportedly resorted to such measures over 2000 years ago. Even at the ancient olympic games, athletes employed special diets and concoctions to enhance their performance. In ancient Rome and ancient Egypt, gladiators and athletes ingested various potions in order to improve their physical endurance. In most in­ stances, such early examples of substance abuse by athletes involved relatively in­ nocuous chemicals, and one might presume that any enhanced performance could be attributed largely to a placebo effect. Nowadays, aside from the ethical issues, these performance-enhancing substances are far more potent and hence toxic to the body. The many performance-enhancing chemicals, drugs, and hormones exert a variety of complex pharmacological actions, but all are meant in some fashion to improve phys­ ical ability. Their pharmacological effects ranges from imprOVed muscle strength, as in the case of anabolic steroids and growth hormone, to central nervous system stimula­ tion, as in the case of caffeine or amphetamine. Analgesics or other pain-killing drugs may also be used to suppress an existing injury in order that the athlete may compete.

This text presents a range of topics from the molecular events surrounding hormone actions to epidemiologic studies of the effects of environmental and occupational chemicals on reproductive organs. The endocrine systems covered include the adrenal cortex, thyroid and parathyroid, gonads, and the endocrine pancreas. Of particular importance are the chapters covering the general characteristics of the estrogen receptors and the androgen receptors. The book also describes some of the underlying toxic mechanisms involving pancreatic B cells and metal-induced changes in male sex accessory glands.