Ovary, hormones produced

Gengva l Examp Ig Queen substance C 5) is a hormone produced by a queen bee to prevent the worker bees ovaries maturing and to train them to serve her. 

Mitochondrial system The function of the mitochondrial cyto chrome P450 monooxygenase system is to participate in the hydroxylation of steroids, a process that makes these hydropho bic compounds more water soluble. For example, in the steroid hormone-producing tissues, such as the placenta, ovaries, testes, and adrenal cortex, it is used to hydroxylate intermediates in the conversion of cholesterol to steroid hormones. The liver uses this system in bile acid synthesis (see p. 222), and the kidney uses it to hydroxylate vitamin 25-hydroxycholecalciferol (vitamin D, see p. 384) to its biologically active 1,25-hydroxylated form. 

Oxytocin is a lessor known hormone produced in several areas of the body including the testes, pancreas, pineal gland, thymus, adrenal glands, and ovaries. So it would seem apparent that this is an important hormone. You don t know the half of it yet. 

Male and female hormones are produced primarily in the gonads. Androgens are synthesized in the testes in the male. In the female, the ovaries are the principal sites of estrogen and progestin production. As discussed in Chapter 29, small amounts of sex-related hormones are also produced in the adrenal cortex in both sexes, which accounts for the fact that small amounts of hormones of the opposite sex are seen in females and males that is, low testosterone levels are seen in females, and males produce small quantities of estrogen. However, under normal conditions, the amounts of sex-related hormones produced by the adrenal cortex are usually too small to produce significant physiologic effects. 

Murray and coauthors (Murray et al. 2001) claim that corticotropin-releasing hormones, catecholamines, neuropeptides, and steroid hormones produced throughout the central nervous system as well as in several peripheral sites including the pituitary, testes, ovaries, heart, adrenals, and immune tissues play an important role in the immunomodulatory mechanism of stress affecting human or animal bodies. 

Endocrine disruption which is independent of interactions between xenobiotics and endogenous hormone receptors can occur in a variety of different ways, including alterations in the number of hormone receptor sites (up- or down-regulation) or direct or indirect hormone modifications which alter hormonal function (Evans, 2007 Keith, 1997). Xenobiotics can change the rate of synthesis or destruction of endogenous hormones and can alter how hormones are stored, how they are released into and/or transported within the circulation, or even how they are eventually cleared from the body (Capen, 2008 Evans, 2007 Keith, 1997 Sikka et al, 2005). Any xenobiotic toxic to hormone-producing organs or tissues (e.g. testis and ovary) also has the potential to decrease hormone synthesis and thereby indirectly cause endocrine disruption (Devine and Hoyer, 2005 Evans, 2007). 

The endocrine system is comprised of a network of hormone-producing glands. These glands include the pituitary, thyroid, adrenal, thymus, pancreas, ovaries, and testes. The hormones produced are released in carefully... 

The nature and quantity of steroid hormones produced by the adrenal glands and gonads are different. The difference is inherent in the degree of activity of certain enzyme systems. For example, the enzymes lip-hydroxylase and 21-hydroxylase, present only in the adrenal glands, synthesize steroids characteristic of the adrenal glands. Similarly the ovaries and the testes contain enzymes that synthesize the male and female sex hormones (see Chapter 53). 

One of the most important placental hormones is CG. CG stimulates the ovary to produce progesterone which, in turn, prevents menstruation thereby protecting the pregnancy. The chemistry, biochemistry, and methods for CG are discussed in the section on laboratory tests later m this chapter. 

The maternal placenta also produces relaxin, a hormone produced by the ovaries. Relaxin causes relaxation of the cervix during parturition. 

In addition to Its structural role In membranes, discussed In Chapter 5, cholesterol Is the precursor for several Important bloactive molecules. They Include bile acids (see Figure 18-6), which are made In the liver and help emulsify dietary fats for digestion and absorption In the Intestines, steroid hormones produced by endocrine cells (e.g., adrenal gland, ovary, testes), and vitamin D produced In the skin and kidneys. Arthropods need cholesterol or other sterols to produce membranes and ecdysterold hormones, which control development however, they cannot make the precursor sterols themselves and must obtain these compounds In their diet. Another critical function of cholesterol Is Its covalent addition to Hedgehog protein, a key signaling molecule In embryonic development (Chapter 15). 

Estrogens. The biosynthetic relationship of the ovarian female sex hormones to androstenedione (their precursor), to cholesterol, and to each other is outlined in Figure 14-6. Estrone [3-hydroxy-l,3,5(10)-estratriene-17-one] was the first sex hormone to be isolated (Doisy et al., 1930 Butenand, 1930). Estradiol, which has been established as the true female sex hormone, is about 10 times more potent than estrone. It was not isolated for five years and took the extraction of 4 tons of sow ovaries to produce a little more than 10 mg of the hormone. Estrone was initially isolated from human pregnancy urine. 

There are several polymers among the active substances. Classical drugs include disinfectant protein silver (Argentum proteinicum) and colloidal silver (Argentum colloidale), which are mentioned in the pharmacopoeias of several countries. Dextran (its sterile solution) is used for plasma supplementation. Polypeptide and macropeptide hormones (e.g. hormones produced in the hypophysis, pancreas, and ovaries), enzymes (e.g. pepsin, pancreatin), polymer antibiotics (e.g. polymixin, vancomycin) must be mentioned. There are several polymer molecules among cytostatic agents, too [13]. 

Steroid hormone production occurs on the smooth endoplasmic reticulum and in the mitochondria of the hormone-producing cells. Cholesterol is the precursor of all steroid hormones. The adrenal cortex produces the glucocorticoids, mineralocorticoids, and androgens, whereas the testes synthesize testosterone and the ovaries produce mainly estrogen and progesterone. The relative concentration of the various enzymes determines the final steroid hormone products [4]. Figure 7.4 shows the main pathways for the synthesis of steroid hormones. 

Hormones are the chemical messengers of the body they are secreted by the endocrine glands and regulate biological processes. Corticosteroids, described in the preceding section, are hormones produced by the adrenal glands. The sex glands— testes in males, ovaries in... 

Gonadal hormones, sex hormones steroid hormones produced in the male (testes) and female (ovaries) gonads. The G.h. determine the male or female character of an organism, in that they effect the... 

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