Anterior pituitary

The anterior pituitary (also called the adenohypophysis) comprises the anterior lobe of the pituitary gland and is part of the endocrine system. Under the influence of the hypothalamus, the anterior pituitary produces and secretes several peptide hormones that regulate many physiological processes including stress, growth, and reproduction. Anterior pituitary - Anatomy and development. The adenohypophysis is a pea-size gland anterior to the neurohypophysis, caudal to the hypothalamus, and sits in the ...

Including:

• Anterior pituitary - Anatomy and development
• Anterior pituitary - Histology
• Anterior pituitary - Physiology
• Anterior pituitary - Major hormones secreted
• Anterior pituitary - Role in disease

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The adenohypophysis is a pea-size gland anterior to the neurohypophysis, caudal to the hypothalamus, and sits in the medial aspect of the brain. Its blood is supplied by the superior and inferior hypophyseal arteries, and it secretes hormones into the hypophyseal vein. The anterior pituitary is derived from the ectoderm of the roof of the embryonic mouth. An outpocketing of this ectoderm forms Rathke's pouch, which pinches off from the oral ectoderm and fuses with the developing posterior pituitary. The anterior wall of Rathke's pouch ...

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Anterior pituitary, Anterior pituitary - Anatomy and development, Anterior pituitary - Histology, Anterior pituitary - Physiology, Anterior pituitary - Major hormones secreted, Anterior pituitary - Role in disease

Read more here: » Anterior pituitary: Encyclopedia II - Anterior pituitary - Anatomy and development

Calcitonin is a a 32 amino acid polypeptide hormone that is produced in humans primarily by the C cells of the thyroid, and in many other animals in the ultimobranchial body. Calcitonin - Synthesis. It is formed by proteolytic cleavage of a larger prepropeptide which is the product of the CALC1 gene, which itself is part of a superfamily of related protein hormone precusors including Islet Amyloid Precursor Protein, Calcitonin Gene-Related Peptide and the precursor of Adrenomedullin.

Adrenocorticotropic hormone (ACTH or corticotropin) is a polypeptide hormone synthesised (from POMC, pre-opiomelanocortin) and secreted from corticotropes in the anterior lobe of the pituitary gland in response to the hormone corticotropin-releasing factor (CRF) released by the hypothalamus. ACTH stimulates the cortex of the adrenal gland and boosts the synthesis of corticosteroids, mainly glucocorticoids but also mineralcorticoids and sex steroids (androgens). Together with ACTH the hormones lipotropin, melanocyte-stimulating hormone (MSH), β-endorphin and met-enkephalin are also release ...

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• Adrenocorticotropic hormone - Related topics

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Corticotropin-releasing hormone (CRH), also called corticotropin-releasing factor (CRF) or corticoliberin, is a polypeptide hormone involved in the stress response. It is produced by the hypothalamus and stimulates corticotropic cells of the anterior lobe of the pituitary to produce ACTH and other biologically active substances (for example β-endorphin). CRH is also synthes ...

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• Corticotropin-releasing hormone - Reference

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Antidiuretic hormone (ADH), also known as arginine vasopressin (AVP), is a hormone that is mainly released when the body is low on water; it causes the kidneys to save water by concentrating the urine and is also involved in the creation of thirst. It is a peptide hormone produced by the hypothalamus, and stored in the posterior part of the pituitary gland. Antidiuretic hormone - Physiology. Antidiuretic hormone - Control. ADH is activated by "water r ...

Including:

• Antidiuretic hormone - Physiology
• Antidiuretic hormone - Control
• Antidiuretic hormone - Actions
• Antidiuretic hormone - Structure and relation to oxytocin
• Antidiuretic hormone - Pharmacology
• Antidiuretic hormone - Role in disease

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PTH acts to increase the concentration of calcium in the blood in three ways. It enhances the release of calcium from the large reservoir contained in the bones, enhances reabsorption of calcium from renal tubules; and enhances the absorption of calcium in the intestine by increasing the production of vitamin D. PTH also acts to decrease the concentration of phosphate in the blood, primarily by reducing re ...

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Parathyroid hormone, Parathyroid hormone - Functions, Parathyroid hormone - Bone resorption, Parathyroid hormone - Syndromes, Parathyroid hormone - Measurements

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In both males and females, LH stimulates the production of sex steroids from the gonads. Leydig cells in male testes respond to LH by producing testosterone, while theca cells in the female ovary respond to LH by producing androgens and estrogens. In females, a LH surge about halfway through the menstrual cycle triggers the onset of ovulation. LH also induces the ovulated follicle to become a corpus luteum, which then secretes progesterone. LH levels are normally low durin ...

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Luteinizing hormone, Luteinizing hormone - Structure, Luteinizing hormone - Genes, Luteinizing hormone - Activity, Luteinizing hormone - Deficient LH activity, Luteinizing hormone - Excess LH activity, Luteinizing hormone - Availability

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All actions of the hormone are inhibitory. Somatostatin's main actions are: inhibits the release of growth hormone (GH) inhibits the release of thyroid stimulating hormone (TSH) suppresses the release of gastrointestinal hormones gastrin cholecystokinin (CCK) secretin motilin vasoactive intestinal peptide (VIP) gastric inhibitory polypeptide (GIP) enteroglucagon (GIP) prolongs gastric emptying, gall bladder contraction and ...

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Somatostatin, Somatostatin - Actions, Somatostatin - Synthetic substitutes

Read more here: » Somatostatin: Encyclopedia II - Somatostatin - Actions

Progesterone exerts its action via the intracellular progesterone receptor. It has a number of physiological effects, usually to counteract effects caused by estrogen. Estrogen is required to induce a progesterone receptor. Progesterone - Reproduction. Progesterone's reproductive function serves to convert the endometrium to its secretory stage to prepare the uterus for implantation. If pregnancy does not occur, progesterone levels will decrease leading to menstruation in the human. Normal menstrual bleedin ...

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Progesterone, Progesterone - Chemistry, Progesterone - Synthesis, Progesterone - Sources, Progesterone - Levels, Progesterone - Effects, Progesterone - Reproduction, Progesterone - Neurosteroid, Progesterone - Other systems, Progesterone - Medical Applications, Progesterone - External link

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Gastrin - Genetics. The GAS gene is located on the long arm of the seventh chromosome (17q21). Gastrin - Synthesis and release. Gastrin is a linear peptide hormone produced by G cells that are located mainly in the antrum of the stomach and the D cells of the pancreatic islets. It is secreted into the bloodstream. Gastrin is found primarily in three forms: gastrin-34 ("big gastrin"), gastrin-17 ("little gastrin"), and gastrin-14 ("minigastrin"). The ...

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Gastrin, Gastrin - Physiology, Gastrin - Genetics, Gastrin - Synthesis and release, Gastrin - Function, Gastrin - Factors influencing secretion, Gastrin - Role in disease, Gastrin - External link

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The hormone participates in calcium and phosphorus metabolism and it was found in fish, reptiles, birds and mammals. Most evidence points to that Calcitonin is not of physiological importance to humans, except for it's pharmacological use (see below). Specifically, calcitonin reduces blood calcium levels in three ways: decreasing calcium absorption by the intestines decreasing osteoclast activity in bones decreasing calcium and phosphate ...

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Calcitonin, Calcitonin - Synthesis, Calcitonin - Physiology, Calcitonin - Pharmacology, Calcitonin - History, Calcitonin - Reference

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Antidiuretic hormone - Control. ADH is activated by "water receptors" in both the extracellular fluid volume and the intracellular fluid volume. In the extracellular fluid the activators are mainly baroreceptors in the veins, atria, and arterioles. In the intracellular fluid the activators are mainly osmoreceptors in the hypothalamus. Ethanol and caffeine block the release of ADH from the posterior pituitary gland. The resulting decrease in water reabsorption in the kidneys leads to a higher volume of urine output. See also:

Antidiuretic hormone, Antidiuretic hormone - Physiology, Antidiuretic hormone - Control, Antidiuretic hormone - Actions, Antidiuretic hormone - Structure and relation to oxytocin, Antidiuretic hormone - Pharmacology, Antidiuretic hormone - Role in disease

Read more here: » Antidiuretic hormone: Encyclopedia II - Antidiuretic hormone - Physiology

Estradiol, like other sex steroids, is derived from cholesterol. After side chain cleavage and either utilizing the delta-5 pathway or the delta-4 pathway androstenedione is the key intermediary. Androstendione is either converted to testosterone which in turn undergoes aromatization to estradiol, or, alternatively, androstendione is aromatized to estrone which is converted to estradiol. Co ...

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Estradiol, Estradiol - Synthesis, Estradiol - Production, Estradiol - Mechanism of action, Estradiol - Effects, Estradiol - Role in sexual differentiation, Estradiol - Therapy, Estradiol - Hormone replacement therapy, Estradiol - Blocking estrogens

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In both males and females, LH stimulates the production of sex steroids from the gonads. Leydig cells in male testes respond to LH by producing testosterone, while theca cells in the female ovary respond to LH by producing androgens and estrogens. In females, a LH surge about halfway through the menstrual cycle triggers the onset of ovulation. LH also induces the ovulated follicle to become the corpus luteum, which then secretes progesterone. LH levels are normally low durin ...

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Luteinizing hormone, Luteinizing hormone - Structure, Luteinizing hormone - Genes, Luteinizing hormone - Activity, Luteinizing hormone - Deficient LH activity, Luteinizing hormone - Excess LH activity, Luteinizing hormone - Availability

Read more here: » Luteinizing hormone: Encyclopedia II - Luteinizing hormone - Activity

Glucagon - Stimulus for increased secretion of glucagon. decreased plasma glucose increased catecholamines increased plasma amino acids (to protect from hypoglycemia if an all protein meal consumed) sympathetic nervous system Glucagon - Stimulus for decreased secretion of glucagon. somatostatin Insulin ...

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Glucagon, Glucagon - History, Glucagon - Physiology, Glucagon - Regulation, Glucagon - Stimulus for increased secretion of glucagon, Glucagon - Stimulus for decreased secretion of glucagon, Glucagon - Function, Glucagon - Mechanism of action, Glucagon - Pathology, Glucagon - Pharmacological application of glucagon, Glucagon - Media

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In both males and females, FSH stimulates the maturation of germ cells. In females, a FSH initiates follicular growth, and with the concomitant rise in inhibin B, FSH levels decline. This seems to be critical to select only the most advanced follicle to proceed to ovulation. FSH levels are normally low during childhood and, in women, high after menopause. ...

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Follicle-stimulating hormone, Follicle-stimulating hormone - Structure, Follicle-stimulating hormone - Genes, Follicle-stimulating hormone - Activity, Follicle-stimulating hormone - Decifient FSH activity, Follicle-stimulating hormone - Availability

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The identity of GNRH1 was clarified by the 1977 Nobel Laureates Roger Guillemin and Andrew V. Schally: pyroGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly CONH2. ...

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Gonadotropin-releasing hormone, Gonadotropin-releasing hormone - Gene, Gonadotropin-releasing hormone - Structure, Gonadotropin-releasing hormone - GNRH1 as a neurohormone, Gonadotropin-releasing hormone - Control of FSH and LH, Gonadotropin-releasing hormone - Activity, Gonadotropin-releasing hormone - GNRH1 in other organs, Gonadotropin-releasing hormone - Medication, Gonadotropin-releasing hormone - Agonists and antagonists

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GNRH1 activity is very low during childhood, and is activated at puberty. During the reproductive years, pulse activity is critical for successful reproductive function as controlled by feedback loops. However, once a pregnancy is established, GNRH1 activity is not required. Pulsatile activity can be disrupted by hypothalamic-pituitary disease, either dysfunction (i.e., hypothalamic suppression) or organic lesions (trauma, tumor). Elevated prolactin levels decrease GNRH1 activity. In contrast, hyperinsulinemia increases pulse activity leading to disordery LH and FSH activity, as seen in Polycystic ovary syndrome (PCOS). G ...

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Gonadotropin-releasing hormone, Gonadotropin-releasing hormone - Gene, Gonadotropin-releasing hormone - Structure, Gonadotropin-releasing hormone - GNRH1 as a neurohormone, Gonadotropin-releasing hormone - Control of FSH and LH, Gonadotropin-releasing hormone - Activity, Gonadotropin-releasing hormone - GNRH1 in other organs, Gonadotropin-releasing hormone - Medication, Gonadotropin-releasing hormone - Agonists and antagonists

Read more here: » Gonadotropin-releasing hormone: Encyclopedia II - Gonadotropin-releasing hormone - Activity

At the pituitary, GNRH1 stimulates the synthesis and secretion of follicle stimulating hormone (FSH) and luteinizing hormone (LH). These processes are controlled by the size and frequency of GNRH1 pulses, as well as by feedback from androgens and estrogens. There are differences in GNRH1 secretion between males and females: in males, GNRH1 is secreted in pulses at a constant frequency, but in females the frequency of the pulses varies during the me ...

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Gonadotropin-releasing hormone, Gonadotropin-releasing hormone - Gene, Gonadotropin-releasing hormone - Structure, Gonadotropin-releasing hormone - GNRH1 as a neurohormone, Gonadotropin-releasing hormone - Control of FSH and LH, Gonadotropin-releasing hormone - Activity, Gonadotropin-releasing hormone - GNRH1 in other organs, Gonadotropin-releasing hormone - Medication, Gonadotropin-releasing hormone - Agonists and antagonists

Read more here: » Gonadotropin-releasing hormone: Encyclopedia II - Gonadotropin-releasing hormone - Control of FSH and LH