Pituitary gland (Гипофиз)

Pituitary gland or Hypophysis

Pituitary gland or Hypophysis

The pituitary gland (means to grow under) is ovoid in shape and is located in the sellaturcica, a bony cavity of the sphenoid bone at the base of brain and connected to thehypothalamic region of the brain by a stalk called infundibulum.

It is about one centimetre in diameter and 0.5 gm in weight. The pituitary consists of two lobes, anterior glandular adenohypophysis and posterior neural neurohypophysis.

The anterior lobe originates from the embryonic invagination of pharyngeal epithelium called Rathke’s pouch and the posterior lobe is originates from the base of the brain as an outgrowth of hypothalamus.

Anatomically the adenohypophysis has three lobes or zones namely pars intermedia, pars distalis and pars tuberalis. The neurohypophysis is otherwise known as pars nervosa.

The anterior lobe of pituitary secretes six tropic hormones such as growth hormone (GH), thyroid stimulating hormone (TSH), adreno corticotropic hormone (ACTH), follicle stimulating hormone (FSH), luteinizing hormone (LH), luteotropic hormone (LTH) and melanocyte stimulating hormone (MSH) (in lower animals only). The posterior lobe of pituitary secretes the hormones namely vasopressin and oxytocin.

Hormones of Adenohypophysis

(i)             Growth hormone (GH): It is also known as somatotropic hormone (STH)or Somatotropin. It is a peptide hormone. Growth hormone promotes growth of all the tissues and metabolic process of the body. It influences the metabolism of carbohydrates, proteins and lipids and increases the rate of protein biosynthesis in the cells.

It stimulates chondrogenesis (cartilage formation), osteogenesis (bone formation) and helps in the retention of minerals nitrogen, potassium, phosphorus, sodium etc., in the body. GH increases the release of fatty acid from adipose tissue and decreases the rate of glucose utilization for energy by the cells.

Thus it conserves glucose for glucose dependent tissues, such as the brain.

ii)             Thyroid stimulating hormone (TSH) or thyrotropin: TSH is aglycoprotein hormone, which stimulates the thyroid gland to secrete Tri-iodothyronine (T3) and thyroxine (T4). TSH secretion is regulated by negative feedback mechanism.

It’s release from the anterior pituitary is induced by the thyrotropin releasing hormone (TRH). When thyroxine level in the blood increases, TRH acts on both the pituitary and hypothalamus to inhibit TSH secretion.

(iii) Adreno cortico tropic hormone (ACTH): ACTH is a peptide hormone thatstimulates the adrenal cortex to secrete glucocorticoids and mineralocorticoids. It stimulates melanin synthesis in melanocytes, induces the release of fatty acids from adipose tissues and stimulates insulin secretion. ACTH secretion is regulated by negative feedback mechanism.

(iv) Follicle stimulating hormone (FSH): FSH is a glycoprotein hormone whichregulates the functions of the gonads (ovary and testis).

In males, FSH along with androgens acts on the germinal epithelium of seminiferous tubules and stimulates the production and release of sperms (spermatogenesis).

In females, FSH acts on the ovaries and brings about the development and maturation of graffian follicles.

(v) Luteinizing hormone (LH): LH is a glycoprotein hormone which is also known asinterstitial cell stimulating hormone (ICSH). In males, ICSH acts on the interstitial cells of testis to produce the male sex hormone, testosterone.

In females, LH along with FSH matures the ovarian follicles. LH independently induces ovulation, maintains the corpus luteum and promotes synthesis and release of ovarian hormones. FSH and LH are collectively referred as gonadotropins. FSH and LH are not produced during childhood.

The secretion of FSH and LH starts only during pre pubertal period.

(vi) Luteotropic hormone (LTH): LTH is also called luteotropin or lactogenic hormoneor prolactin or mammotropin. It is a protein hormone which stimulates milk secretion after the child birth in females. High prolactin secretion during lactation suppresses LH secretion and ovulation since it induces the corpus luteum hence named as luteo tropic hormone.

Hormones of neurohypophysis

i. Vasopressin or antidiuretic hormone (ADH) : ADH is a peptide hormone whichpromotes reabsorption of water and electrolytes by distal tubules of nephron and thereby reduces loss of water through urine.

Hence it is called as anti diuretic hormone. It also causes constriction of blood vessels when released in large amount and increases blood pressure.

ADH deficiency causes Diabetes insipidus which induces the production of large amount of urine.

ii. Oxytocin (means quick birth): It is a peptide hormone which stimulates vigorouscontraction of the smooth muscles of uterus during child birth and ejection of milk from the mammary glands.

Источник: https://www.brainkart.com/article/Pituitary-gland-or-Hypophysis_33273/

Pituitary gland

Previous (Pitirim Sorokin)

Pituitary glandLatin

Gray's

Artery

Precursor

MeSH

Dorlands/Elsevier

Located at the base of the skull, the pituitary gland is protected by a bony structure called the sella turcica of the sphenoid bone

Median sagittal through the hypophysis of an adult monkey Semidiagrammatic

hypophysis, glandula pituitaria

subject #275 1275

superior hypophyseal artery, infundibular artery, prechiasmal artery, inferior hypophyseal artery, capsular artery, artery of the inferior cavernous sinus[1]Vein =

neural and oral ectoderm, including Rathke's pouch

Pituitary+Gland

h_22/12439692

The pituitary gland, or hypophysis, is an endocrine gland located near the base of vertebrate brain, and that produces secretions that stimulate activities in other endocrine glands, impacting metabolism, growth, and other physiological processes. The pituitary gland is sometimes called the «master gland» of the body, since all other secretions from endocrine glands depend on stimulation by the pituitary gland.

In general, the cells, tissues, and organs of the endocrine system make hormones, which complement the nervous system in carrying out coordinating functions.

The most complex organ of the endocrine system, both functionally and structurally, is the pituitary gland.

This gland is found in all vertebrates—mammals, birds, reptiles, amphibians, and fish—and is similar in location, structure, and function in these diverse groups.

The pituitary gland reveals aspects of the remarkable coordination within vertebrates. Hormones produced in this gland at the base of the brain travel to other parts of the body, impacting particular targeted cells. After the desired impact is made, homeostasis is restored.

Underlying all of this harmony is the concept of dual purposes, whereby the pituitary gland both advances its own maintenance and development (taking in nutrients, eliminating wastes, etc.) while providing a function for the entire body.

These two function work together—only by having a healthy pituitary can the body be aided.

Overview

In vertebrates, the pituitary gland is actually two fused glands, the anterior pituitary and the posterior pituitary. Each gland is made up of different tissue types. Some verterbrates, fish, however, have a third distinct intermediate section.

In humans, the pituitary gland is about the size of a bean and sits at the base of the brain. It is located in a small, bony cavity called the pituitary fossa, which is situated in the sphenoid bone in the middle cranial fossa. The pituitary gland is connected to the hypothalamus of the brain by the infundibulum and is covered by the sellar diaphragm fold.

The individual glands (anterior and posterior pituitary) merge during embryonic development. The tissue that forms the roof of the mouth also forms the anterior pituitary, a true endocrine gland of epithelial origin. The posterior pituitary, on the other hand, is an extension of neural tissue.

The pituitary gland as it is known in humans is described in greater detail below.

The pituitary gland secretes various hormones regulating homeostasis, including trophic hormones that stimulate other endocrine glands. It also secretes hormones for sexual eminence and desires. Research has shown the importance of the anterior pituitary in the controlling of the sex cycle in vertebrates.

Sections

Located at the base of the brain, the pituitary is functionally linked to the hypothalamus. It is divided into two lobes: the anterior or front lobe (adenohypophysis) and the posterior or rear lobe (neurohypophysis).

Anterior pituitary (adenohypophysis)

The anterior lobe is derived from the invagination of the oral musocsa called Rathke's pouch. The lobe is usually divided into three regions:

• pars distalis («distal part») — the majority of the anterior pituitary
• pars tuberalis («tubular part») — a sheath extending up from the pars distalis and wrapping around the pituitary stalk
• pars intermedia («intermediate part») — sits between the bulk of the anterior pituitary and the posterior pituitary; often very small in humans

The function of the tuberalis is not well characterized, and most of the rest of this article refers primarily to the pars distalis.

The anterior pituitary is functionally linked to the hypothalamus via the hypophyseal-portal vascular connection in the pituitary stalk. Through this vascular connection, the hypothalamus integrates stimulatory and inhibitory central and peripheral signals to the five phenotypically distinct pituitary cell types.

The anterior pituitary synthesizes and secrets six important endocrine hormones:

• Adrenocorticotropic hormone (ACTH)
• Thyroid stimulating hormone (TSH)
• Prolactin
• Growth hormone (also called somatotrophin)
• Follicle stimulating hormone (FSH)
• Leutinizing hormone (LH)

These hormones are released from the anterior pituitary under the influence of hypothalamic hormones.

The hypothalamic hormones travel to the anterior lobe by way of a special capillary system, called the hypothalamic-hypophyseal portal system.

Once the hormone is released, it either targets another gland (or organ) or it controls the secretion of another hormone from a gland. In that case, the first hormone is called a trophic hormone.

The control of hormones from the anterior pituitary exerts a negative feedback loop. Their release is inhibited by increasing levels of hormones from the target gland on which they act.

Posterior pituitary (neurohypophysis)

Despite its name, the posterior pituitary gland is not a gland, per se; rather, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary gland. Classification of the posterior pituitary varies, but most sources include the three regions below:

• pars nervosa, or neural/posterior lobe — constitutes the majority of the posterior pituitary, and is sometimes (incorrectly) considered synonymous with it
• infundibular stalk — also known as the «infundibulum» or «pituitary stalk»; the term «hypothalamic-hypophyseal tract» is a near-synonym, describing the connection rather than the structure
• median eminence — this is only occasionally included as part of the posterior pituitary; some sources specifically exclude it

The posterior lobe is connected to the hypothalamus via the infundibulum (or stalk), giving rise to the tuberoinfundibular pathway.

Hormones are made in nerve cell bodies positioned in the hypothalamus, and these hormones are then transported down the nerve cell's axons to the posterior pituitary.

They are stored in the posterior pituitary in cell terminals until a stimulus reaches the hypothalamus, which then sends an electrical signal to the posterior pituitary to release the hormone(s) into circulation.

The hormones released by the posterior pituitary are:

• Oxytocin
• Antidiuretic hormone (ADH, also known as vasopressin and AVP, arginine vasopressin)

Intermediate lobe

There is also an intermediate lobe in many animals. For instance, in fish it is believed to control physiological color change.

In adult humans, it is just a thin layer of cells between the anterior pituitary and posterior pituitary, nearly indistinguishable from the anterior lobe.

The intermediate lobe produces melanocyte-stimulating hormone or MSH, although this function is often (imprecisely) attributed to the anterior pituitary.

Functions

The pituitary gland helps control the following body processes through secretion and release of various hormones:

• Human development and growth — ACTH and GH
• Blood pressure (through water reabsorption)— ADH/vasopressin
• Some aspects of pregnancy and childbirth, including stimulation of uterine contractions during childbirth — oxytocin
• Breast milk production — prolactin
• Sex organ functions in both women and men — FSH and LH
• Thyroid gland function — TSH
• Metabolism (conversion of food into energy) — TSH
• Water and osmolarity regulation in the body (in kidneys)— ADH/vasopressin

Pathology

Variances from normal secretion of hormones can cause a variety of pathologies in the human body. Hypersecretion of a hormone exaggerates its effects, while hyposecretion of a hormone either diminishes or all together eliminates the effects of the hormone. Common disorders involving the pituitary gland include:

Condition	Direction	Hormone
Acromegaly	overproduction	growth hormone
Growth hormone deficiency	underproduction	growth hormone
Syndrome of inappropriate antidiuretic hormone	overproduction	vasopressin
Diabetes insipidus	underproduction	vasopressin
Sheehan syndrome	underproduction	prolactin
Pituitary adenoma	overproduction	any pituitary hormone
Hypopituitarism	underproduction	any pituitary hormone

Notes

1. ↑ Gibo, H., M. Hokama, K. Kyoshima, and S. Kobayashi. 1993. “Arteries to the pituitary.” Nippon Rinsho 51(10): 2550-2554. PMID 8254920.

Источник: http://www.newworldencyclopedia.org/entry/Pituitary

Pituitary Gland

Gale Encyclopedia of Nursing and Allied Health
COPYRIGHT 2006 Thomson Gale

The pituitary gland is located at the base of the brain and is part of the endocrine system . It is sometimes called the hypophysis, from two Greek words that mean «to grow beneath.» The pituitary is responsible for the hormonal regulation of several body processes, including water retention, breast milk synthesis and release, human growth, and thyroid gland secretions.

Description

The pituitary is one of the most extensively researched glands in the endocrine system. In humans, it is located at the base of the brain just beneath the hypothalamus.

There are three separate lobes (or sections) of the pituitary: the anterior lobe, the posterior lobe and the intermediate lobe. Therefore, it is sometimes considered as three different glands.

In addition, there is a small stem called the pituitary stalk that connects the pituitary to the hypothalamus.

The pituitary gland is formed during early fetal development . An understanding of its formation explains its position in the endocrine system as well as its neurological importance. Early in the development of the fetus, a small sac of cells forms at the top of the oral cavity and moves upward.

These cells are known as Rathke's pouch. At the same time, a small fold of neural tissue extends downward from the hypothalamus.

During fetal development, the two structures continue to move toward each other; they meet and fuse to form the anterior (originally Rathke's pouch) and posterior (from the hypothalamus) lobes of the pituitary.

The hypothalamus, which is located just above the pituitary gland, is a region in the forebrain that is responsible for regulating all lobes of the pituitary.

The pituitary releases, but does not necessarily synthesize, nine different hormones. Neurohormones are synthesized by the hypothalamus and transported to the posterior pituitary.

The release of hormones from each lobe of the pituitary is regulated differently.

Anterior pituitary

The anterior pituitary is sometimes called the adenohypophysis. It constitutes about 80% of the pituitary by weight. The cells of the anterior pituitary act true endocrine cells.

Instead of containing neurons , the anterior pituitary receives chemical signals through the blood and releases hormones in response. It has a direct connection with the hypothalamus through blood vessels .

Various cells in the anterior pituitary release the following hormones:

• Gonadotrophs release luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
• Lactotrophs release prolactin (PRL).
• Corticotrophs release adrenocorticotropic hormone (ACTH).
• Somatotrophs release growth hormone (GH).
• Thyrotrophs release thyroid-stimulating hormone (TSH).

Posterior pituitary

The posterior pituitary is sometimes referred to as the neurohypophysis because it acts an extension of the nervous system.

As opposed to the anterior pituitary, which is connected to the hypothalamus via the circulatory system, the posterior pituitary receives nerve impulses from the same nerve cells that innervate the hypothalamus.

The posterior pituitary releases oxytocin and antidiuretic hormone (ADH, or vasopressin).

Intermediate pituitary

The intermediate lobe is not a complete «lobe» in humans. Instead it is a simple structure comprised of just a few cells. The intermediate pituitary is an important structure in many lower vertebrates, but it has very little significance in humans. In lower vertebrates, the intermediate

KEY TERMS

Acromegaly —Abnormal enlargement of such parts of the body as the hands, face, head, and feet.

Adenohypophysis —Another name for the anterior lobe of the pituitary.

Antidiuretic hormone (ADH) —A hormone released by the posterior lobe of the pituitary gland that increases the absorption of water by the kidneys. It is also known as vasopressin.

Diabetes insipidus —A disorder characterized by increased urine production resulting from inadequate levels of ADH.

Gonadotropins —Hormones that affect the development or activity of the ovaries or testes.

Hypophysis —Another name for the pituitary gland.

Hypopituitarism —A condition produced by deficient activity of the anterior lobe of the pituitary gland. It is characterized by obesity, incomplete sexual maturation, and in extreme cases, dwarfism.

Hypothalamus —A region in the forebrain that regulates the functions of the autonomic nervous system by vascular communication. The hypothalamus governs the functions of both lobes of the pituitary gland.

Neurohypophysis —Another name for the posterior lobe of the pituitary.

Oxytocin —A hormone produced by the posterior pituitary that stimulates the movement of breast milk from the sacs in which the milk is produced to the larger ducts from which the milk is ejected.

Peptide —A compound containing two or more amino acids, in which the carboxyl group of one acid is linked to the amino group of the other.

Vasopressin —Another name for ADH.

pituitary releases melanocyto-stimulating hormone. This hormone stimulates the growth of melanocytes, which are cells that produce a dark pigment called melanin.

Function

The pituitary gland is an organ that is part of the endocrine system, along with many other glands and organs. It is regulated by the hypothalamus, and it in turn regulates the secretion of many different hormones that are essential to human health.

Role in human health

Hormones released from the anterior and posterior pituitary have far-reaching effects on many different organ systems and physiological processes.

Hormones of the anterior pituitary

Luteinizing hormone and follicle stimulating hormone are called gonadotropins. As the name suggests, the target tissues of these hormones are the gonads (ovaries and testes). They have two main functions.

The first is to promote the development and maturation of sperm and eggs. Second, they stimulate the production and release of such sex steroid hormones as estradiol and testosterone in women and men respectively.

Prolactin is responsible for stimulating cells in the female breast to produce milk.

Therefore, lactotrophs located in the anterior pituitary of women that are breast-feeding are large and numerous, indicating an increased amount of prolactin production.

These lactotrophs comprise about 30% of the cells in the anterior pituitary. The pituitary in women doubles in size during pregnancy because of the increase in size and number of lactotrophs.

The target tissue of adrenocorticotropic hormone is the adrenal cortex (part of the adrenal gland that is located above the kidney). ACTH stimulates the production of cortisol and also causes the cells of the adrenal gland to grow. Cortisol has many effects on metabolism in various tissues.

Growth hormones have many different target tissues and promote the growth of each of them. For this reason human growth hormone (GH) is considered an anabolic hormone, indicating that it is responsible for building tissue proteins . For example, GH directly increases protein synthesis in muscles and the liver ; and it decreases the size of adipose tissue.

It also has an indirect effect by stimulating other hormones. Growth hormones indirectly affect the bones by increasing protein synthesis, collagen synthesis and cell proliferation. In many other tissues, the indirect effects of growth hormone are responsible for protein, RNA and DNA synthesis.

The overall effect of growth hormone is to promote skeletal growth and a lean body mass.

As its name implies, thyroid-stimulating hormone (TSH) promotes cell growth in the thyroid gland. TSH also triggers the secretion of thyroid hormones that affect many metabolic processes in the body.

Hormones of the posterior pituitary

Both oxytocin and antidiuretic hormone (ADH) are peptide hormones that are synthesized in the cell bodies of the nerves originating in the hypothalamus and then delivered through the axons to the posterior pituitary. Thus, they are good examples of neuroendocrine hormones.

The primary target organ of ADH is the kidney. ADH is responsible for increasing water retention by the kidney, resulting in an increase in extracellular fluid and a decrease in urine volume.

Receptors in the hypothalamus called osmoreceptors can sense the concentration of water in the extracellular fluid through changes in extracellular fluid osmolarity. The osmoreceptors in turn determine the release of ADH by the posterior pituitary.

The consumption of alcohol decreases the amount of ADH released. As a result, more fluid is lost through urination, resulting in excessive water loss and thirst.

The primary site of action of oxytocin is female breast tissue. Oxytocin stimulates the contraction of smooth muscle cells in the breast, transferring milk from the place of synthesis to the larger ducts of the breast.

Oxytocin is secreted by the stimulation of touch sensors when an infant is suckling. Other psychological factors, such as the sound of a baby crying, can stimulate the release and action of oxytocin. The role of oxytocin in the onset of labor contractions is not fully clear.

There is no known stimulus for the secretion of oxytocin in the human male.

Hypopituitarism

Disorders of the pituitary gland can have severe effects on normal growth and sexual maturation.

A general condition known as hypopituitarism , also known as pituitary dwarfism, is characterized by a decrease in one or more of the hormones produced by the anterior pituitary.

Sexual immaturity and metabolic dysfunction leading to obesity are symptoms of this syndrome. When hypopituitarism occurs in childhood, growth is slowed. Tumors are often the cause of hypopituitarism; however, sometimes there is no identifiable cause.

If there is a decrease in the levels of hormones released from the hypothalamus, then hypopituitarism results. The symptoms vary according to the number and amount of hormones that are deficient. The most effective treatment is the administration of replacement hormones.

Hyperpituitarism

The overproduction of growth hormone during childhood produces a condition known as gigantism or acromegaly. Excessive secretion of anterior pituitary hormones is known as hyperpituitarism. Growth hormone influences the overgrowth of the skeleton and all other tissues. A person may grow to 8 ft (2.4 m) or more in height.

It is still unclear, but researchers think that over-production of growth hormone may be caused by an adenoma (tumor) on the anterior pituitary. Sometimes, this condition occurs in more than one member of the family, suggesting that there is a genetic component.

Gigantism is treated by removing the tumor and administering medications (bromocriptine and octreotide) that inhibit the production of growth hormone.

Diabetes insipidus

A disorder related to both the hypothalamus and the posterior lobe of the pituitary is diabetes insipidus, not to be confused with diabetes mellitus . Diabetes insipidus, or DI, is caused by a deficiency of antidiuretic hormone (ADH). As a result, water is rapidly released from the body through large volumes of urine (3–30 quarts per day).

DI may result from an inherited trait; from damage to the hypothalamus, which synthesizes ADH; or from damage to the posterior pituitary, which stores the ADH. Diabetes insipidus occurs more frequently in men than in women. In mild cases, no treatment is necessary other than water replacement.

In extreme cases, the patient can be treated by hormone replacement therapy.

BOOKS

Cahill, Matthew, ed. Professional Guide to Diseases. 6th ed. Springhouse, PA: Springhouse Corporation, 1998.

Greenspan, Francis S., and David G. Gardner. Basic and Clinical Endocrinology. 6th ed. New York: Lange Medical Books/McGraw-Hill, 2001.

«Hypothalamic-Pituitary Relationships.» Chapter 6 in The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 1999.

Martin, John H., PhD. Neuroanatomy: Text and Atlas. 2nd ed. Norwalk, CT: Appleton & Lange, 1996.

«Pituitary Disorders.» Chapter 7 in The Merck Manual of Diagnosis and Therapy, edited by Mark H. Beers, MD, and Robert Berkow, MD. Whitehouse Station, NJ: Merck Research Laboratories, 1999.

Vander, Arthur, et al, eds. Human Physiology: The Mechanisms of Body Function, 7th ed. Boston, MA: WBC/McGraw-Hill, 1998.

Sally C. McFarlane-Parrott

Источник: https://www.encyclopedia.com/medicine/anatomy-and-physiology/anatomy-and-physiology/pituitary-gland

Какие гормоны отвечают за здоровье нашего организма

Каждая железа внутренней секреции устроена так, чтобы их деятельность была незаменимой во многих происходящих процессах в организме.

Если хорошо разобраться во всей этой замысловатой системе, то прояснится такая картина: гормоны являются регулировщиками практически каждой функции нашего сложного организма. На некоторые из них полностью влияет выработка гормонов, а на некоторые только частично.

От этой составляющей организма зависят даже самые важные физиологические показатели: рост, умственное развитие, сон, бодрствование, эмоции, возможность продолжать род и т.д.

По всему человеческому организму равномерно расположились так называемые «Фабрики гормонов», а если говорить научным языком, то это — эндокринные железы и те железы, которые состоят из эндокринной ткани. А теперь давайте подробнее рассмотрим все места выработки гормонов, и значение последних для организма человека и его жизни в целом.

Гипофиз (pituitary gland)

Эта железа расположилась в самом основании головного мозга. Она вырабатывает такие виды гормонов:

• Пролактин;
• Гормон роста;
• Гонадотропный гормон;
• Тиреотропный гормон;
• Вазопрессин;
• Адренокортикотропный гормон;
• Окситоцин;
• Мелинотропин.

В его основные обязанности входит ответственность за рост, правильный обмен веществ, поддержание репродуктивной функции и плотности тканей. Мало того, данная железа имеет возможность контролировать функции всех остальных желез и даже выработку ими гормонов.

Гипофиз несет ответственность за сохранение большинства органов или за их укрепление (головной мозг, сердце, кровеносные сосуды, почки, костная ткань, иммунная система). От того насколько хорошо функционирует гипофиз зависит продолжительность жизни человека.

Все случаи гигантизма либо же акромегалии тоже зависят от гипофиза. Такие нарушения случаются в результате повышения секреции его гормонов. И, наоборот, при понижении происходит недостаточность гипоталамо-гипофизарная.

Гипоталамус (hypothalamus)

Это уже целый отдел головного мозга, который представляет собой центр, в котором происходит регуляция всех вегетативных функций.

Если сравнить все функции организма с уровневой системой, то гипоталамус будет находиться на высшем уровне ее функциональных возможностей.

Гипоталамус, имея возможность воздействовать с широким кругом остальных желез внутренней секреции, контролирует процессы репродуктивной функции, лактации, поддержания гомеостаза.

Из этого следует вывод, что если поражается гипоталамус, то это приводит к серьезным нарушениям большинства функций организма. В таких случаях нарушаются все процессы, связанные с обменами веществ (водно-солевой, белковый, липидный, углеводный, тепловой и другие). Начинают развиваться патологические синдромы и эндокринные заболевания.

Эпифиз (pineal gland)

Напоминает образование округлой формы небольших размеров, которое расположено в черепной коробке под полушариями головного мозга. Со стороны эпифиз похож на шишку, поэтому его часто называют «шишковидная железа». Это практически стало его вторым названием.

Орган регулирует суточные ритмы организма, и отвечает за его адаптацию к тем условиям окружающего мира, которым свойственно меняться (например, смена часовых поясов, освещение при перемене день-ночь).

Шишковидное тело вырабатывает гормоны, которые могут вызывать угнетающее действие функций мозга (мелатонин и гломерулотонин).

В случае неправильной работы эпифиза в человека нарушаются биологические ритмы, встречаются расстройства сна.

Щитовидная железа (thyroid gland)

Место расположения — передняя сторона шеи. Она создана из двух долей.

Продуцирует такие три гормона:

• Тироксин;
• Тиреокальцитонин;
• Трийодтиронин.

Все они играют непосредственную роль в процессах регуляции обменов веществ, а также влияют на работу сердечно-сосудистой системы. Только под их воздействием центральная нервная система может нормально развиваться и функционировать.

Щитовидную железу напрямую контролирует гипофиз своей передней долей и теми гормонами, которые она синтезирует.

Поэтому все основные заболевания щитовидной железы связаны с нарушением работы именно гипоталамо-гипофизарной системы.

При чем если тиреоидов вырабатывается намного больше положенного, то это также является нарушение и может вызвать токсический диффузный зоб. Такие сбои в организме совсем маленького ребенка могут спровоцировать слабоумие.

Надпочечники (adrenals glands)

Эта железа функционирует в паре, то есть их две. Спрятаны за брюшинной над верхом почек. Вырабатывают следующие гормоны:

• Кортикостерон;
• Гидрокортизон;
• Альдостерон;
• Кортизон;
• Андрогены;
• Прогестерон;
• Дезоксирокортикостерон;
• Норадреналин;
• Эстрогены;
• Адреналин.

Спектр влияния : тонус сосудов, обменный процесс веществ, качество иммунитета, регуляция обмена водно-электролитного, нормализация процессов жировых, белковых, углеводных.

Поджелудочная железа (pancreas)

Железа, которая одновременно умудряется отвечать за две функции: внутреннюю секрецию и за слаженную работу пищеварительной системы. Ее основные задачи — выработка инсулина и глюкагона. Эти два гормона полностью отвечают за правильный углеводный обмен, а также за нормальный уровень сахара, который находится в крови человека.

В случае поражения той части поджелудочной железы, которая отвечает за производство гормона, падает секреция инсулина, нарушается углеводный обмен, а после этого начинает развиваться сахарный диабет. Так, что развития сахарного диабета во многом зависит от работы поджелудочной железы.

Яичко

Эта железа имеется только в мужском организме. Она парная. Основные функции: секреция половых гормонов у мужчин и выработка сперматозоидов.

В этой железе синтезируются андрогены и самое большое количество тестостерона. От уровня таких гормонов зависит направленность организма на мужской тип, правильность развития именно мужских половых органов, а главное – либидо.

Яичник

А вот яичник – это железа женщин и она, также как яичко, парная. Гормоны: эстрогены, прогестерон и в малых дозах – андрогены. С их помощью организм начинает формировать все женские признаки: гениталии и вторичные половые признаки.

Также эти гормоны играют большую роль в подготовке организма женщины к будущей беременности, родам и лактации. Вышеупомянутые гормоны принимают непосредственную роль в балансировке некоторых обменных процессах (водном, углеводном, минеральном).

Иммунная система и различные органы также поддерживают свои функции, подпитываясь этими гормонами.

Сделав выводы, мы приходим к такому мнению, что организм просто не может нормально функционировать во время сбоя, какой-либо из желез. Ведь именно они являются базами производства и хранения гормонов.

Для написания данной статьи были использованы материалы из книги «Как продлить свою молодость», авторы Тьерри Эртог и Жюль-Жак Набе.

Источник: http://presentway.com/gde-zhivut-gormony-v-tele-cheloveka/