The ovaries are a paired organ located in the pelvic cavity on the back leaf of its own ligament. The length of each ovary is 3-4 cm, width 2-2.5 cm, weight 6-7 g. The surface of the ovary is represented by a layer of cells of the embryonic epithelium. Under it is a dense connective tissue capsule (protein shell). The ovary consists of two substances – the outer cortex and the inner cerebral. The latter has a loose connective tissue base, embryonic remnants of the primary kidney ducts (wolf ducts) and a rich network of blood circulatory necromas. The place where the vessels enter the ovary is called the gateway.

In the gate of the ovary there are nests of cells resembling
testicular glandulocytes (Leydig cells). These cells can secrete androgens. Blood supply to the ovaries occurs mainly due to the ovarian artery and the ovarian branch of the uterine artery. Innervation of the ovaries is very complex and is carried out mainly due to sympathetic nerve fibers.

In the cortex, germ cells are located — egg cells surrounded by rows of granulosa cells and an internal theca (follicles) that are at various stages of development. The stroma around the maturing follicle consists of the cells of the external tire (cells of the external teka, connective tissue layer) and the cells of the internal tire of the follicle (cells of the internal teka, epithelial layer).

The thickened layer of the follicular epithelium lining the inner wall of the follicle is called the granular layer (granulosis zone). Primordial follicles develop from the primordial epithelium in the ovary. By the time of ripening, the number of primordial follicles is about 40,000. With the onset of puberty, only an insignificant part of primordial follicles (approximately Vioo) alternately develop into a mature follicle, the vesicle of the ovarian follicle (grapha vesicle).

The remaining primordial follicles undergo a reverse development, not reaching the stage of the vesicular ovarian follicle. The duration of follicle maturation is 12-14 days. A follicle containing an enlarged ovocyte, having moved to the surface of the ovary, bursts (ovulation). The latter occurs between the 14th and 16th days of the menstrual cycle. The ovocyte is secreted into the abdominal cavity, and then enters the fallopian tubes, where it turns into an oida, a mature egg cell and is subjected to fertilization. In place of the vesicular ovarian follicle, a yellow body is formed from the granulosa cells and the internal theca. In the ovary, two female hormones are produced – progesterone and estradiol.

The corpus luteum produces progesterone. Some progesterone also produces a maturing follicle (granulosa cells). When pregnancy occurs, progesterone is also formed in the placenta. Progesterone in the uterus creates conditions for the perception of the fertilized egg and the bearing of the fetus, inhibits contractile muscle excitability of the skating rink, stimulates the growth of alveoli in the mammary glands, and suppresses the effect of estrogen on the uterine mucosa in the menstrual cycle.

In the liver, progesterone is converted to pregnandiol, which combines with glucuronic acid and is excreted in the urine. In the absence of egg fertilization, the corpus luteum functions for 10–12 days, and then undergoes reverse development and menstruation occurs. It lasts usually 3-5 days. The duration of the menstrual cycle is individual and is 21–24–28–30 days. During fertilization of the egg, the corpus luteum functions for 3V2–4 months and is called the corpus luteum of pregnancy. At the end of pregnancy, it also undergoes reverse development.

Estradiol is mainly produced in granulosa cells.
and internal theca. In small quantities, estrogens are produced in the corpus luteum and in the reticular zone of the adrenal cortex. The most active estrogen is estradiol. Hormonal properties of estradiol metabolism – estrone and estriol (the least active) also. Estrogens help to increase the size of the uterus, vagina, proliferation of the endometrium and myometrium, ensure the development of female secondary sexual characteristics (development of the mammary glands, the formation of a feminine figure and corresponding features of the skeleton) and accelerate the differentiation and ossification of the skeleton, having a protein-anabolic effect. Cells of the internal theca and collar of the ovary produce a small amount of androgens.

After entering the blood, most of the estrogens circulate in it in combination with proteins, glucuronic and sulfuric acids.
and only a small part – in a free state. Inactivation of estrogens occurs mainly in the liver, partly in the lungs, uterus, kidneys, etc. From the liver, estrogens come from the bile into the intestine, from which they are partially absorbed into the blood. The secretion of estrogen from the body occurs mainly with urine (about 65%) and in a small amount with feces (about 10%). With urine, estradiol is excreted in the form of estradiol, estriol and estrone.

local_offerevent_note December 17, 2018

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