Oh

Progesterone 17/3-Estradiol nllOH

nllOH

Estrone 16a-Estriol

Dehydroepiandrosterone (DHEA)

figure 13-5 Structures of the important steroid hormones for the female (see also Figures. 2-23 and 2-30).

sulfate, which is provided by the adrenal cortex of the fetus (see Figure 14-10).

As reviewed in Chapter 2, the naturally occurring progesterones have 21 carbons, with an oxo functionality on both C-3 and C-20. The principal progestin produced by the corpus luteum is progesterone. Small quantities of 20/3-hydroxyprogesterone, 10a-hydroxyprogesterone, and 17a-hydroxy progesterone are also secreted. Figure 2-20 reviews the pathways of biosynthesis of the principal progestins in the nonpregnant female. Progesterone plays an indispensable role in the maintenance of pregnancy (see Figure 14-9).

2. Secretion Rates

The secretion rates of the various steroids produced by the ovaries and corpus luteum have been estimated either by careful determination of their concentration in the periphery and ovarian vein coupled with a measurement of the ovarian blood flow or by use of radioisotopes.

Table 13-2 tabulates the changes that occur in the secretion rate, plasma concentration, and metabolic clearance rates of the principal steroids produced by

TABLE 13-2 Plasma Levels, Production Rates, and Metabolic Clearance of Steroid Hormones Produced by the Human Ovaries"

Ovarian secretion rate Metabolic clearance rate'1 Total plasma concentration

TABLE 13-2 Plasma Levels, Production Rates, and Metabolic Clearance of Steroid Hormones Produced by the Human Ovaries"

Ovarian secretion rate Metabolic clearance rate'1 Total plasma concentration

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Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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