Maturation steroid hormones

Upon entering the cell, the steroid molecule initially binds to the steroid receptor protein (E domain) to form the steroid-hormone-receptor complex. This complex concomitantly binds to an additional eight or more other peptides (also via the E domain) these peptides are termed chaperone peptides and consist of macromolecules such as heat shock proteins (e.g., hsp70, hsp90). The chaperone peptides help to twist and turn the steroid receptor protein into an improved three-dimensional shape for final and optimal binding of the steroid molecule. Following binding of the chaperone peptides, the steroid-hormone-receptor complex becomes a mature steroid-hormone-receptor... 

In humans, most steroids function as hormones, chemical messengers that are secreted by endocrine glands and carried through the bloodstream to target tissues. There are two main classes of steroid hormones the sex hormones, which control maturation, tissue growth, and reproduction, and the adrenocortical hormones, which regulate a variety of metabolic processes. 

With the maturation of tandem mass spectrometry (MS/MS) instruments and methodologies, many commercial laboratories are switching to this technique, and high-sensitivity measurements on high volumes of samples are becoming routinely achieved. Since the future of steroid hormone analysis is MS/MS, only MS techniques will be described in this chapter. Immunoassay procedures have been well described and reviewed over the years and will cease to be mainstream methodologies within the next decade. 

Reproductive organs are the primary source of the steroid hormones that influence sexual and reproductive functions. In men, the testes produce testosterone and similar androgens that are responsible for spermatogenesis and the secondary sexual characteristics of adult males.7,26 In women, sexual maturation and reproductive function are governed by the production of estrogens and progestins from the ovaries.27 The release of male and female sex steroids is controlled by hormones from the hypothalamus and anterior pituitary.32 The control of male and female hormone activity and the pharmacologic implications of these hormones are discussed in Chapter 30. 

The male reproductive tract consists of the (i) testes, which serve as the site of gamete and steroid hormone production, (ii) excurrant ducts and epididymes for the transport, maturation, and storage of sperm, (iii) accessory sex glands for the production of seminal fluid, and (iv) penis, for copulation and delivery of mature sperm to the female reproductive tract. 

Radioimmunoassay (RIA) of steroid hormones, a rapidly maturing branch of biochemistry, forms the subject of a monograph.The method depends upon the ability of certain proteins to bind steroids selectively and reversibly ... 

The majority of studies correlating CD with tumor progression and prognosis have used an immunoradiometric assay that detects both the proforms and mature forms of CD. This assay can be used to measure CD in tissue extract generated for detection of steroid hormone receptors. CD has also been measured by western blot, by immunohistochemistry, and by activity. 

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