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Physiologic anatomical peculiarities of endocrine system in children. Methodics of endocrine glands investigation. Semiotics of hypo- and hyperfunction of some endocrine glands and diseases of the endocrine system . By Nykytyuk S. The endocrine glands consist of. 1.Hypotalamus 2.Hypophysis
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Physiologic anatomical peculiarities of endocrine system in children. Methodics of endocrine glands investigation. Semiotics of hypo- and hyperfunction of some endocrine glands and diseases of the endocrine system.By Nykytyuk S
The endocrine glands consist of 1.Hypotalamus 2.Hypophysis 3.the epiphysis 4.the thyroid gland 5.the parathyroid glands 6.the thymus 7.the islands of Langerhans in the pancreas 8.the adrenal glands 9.the gonads (testis and ovaries)
The main function of the endocrine system 1.to take an active part in metabolism 2.influence on water-mineral metabolism 3.influence on growth and development of a child 4.regulation of differentiation of tissues 5.ensuration of adaptation of the organism to its enviroment
embriology Pituitary, thyroid, adrenal-begin to function during the intrauterine period The hypophysis is organized at 4 weeks of gestation Starts to secrete ACTH at 9-10 weeks
Close relationship between functions of the endocrine system and those of the hypotalamus
1.Pineal gland 2.Pituitary gland 3.Thyroid gland 4.Thymus 5.Adrenal gland 6.Pancreas 7.Ovary 8.Testis Major endocrine glands. (Male left, female on the right.)
The hypotalamus regulates activity • The hypotalamus regulates activity of the hypophysis by producing neurohormones (releasing hormones). • Some of them activate and others inhibit secretion of trophic hormones of the hypophysis
Hypothalamus produces Thyrotropin-releasing hormone (TRH) Gonadotropin-releasing hormone (GnRH) Growth hormone-releasing hormone (GHRH) Corticotropin-releasing hormone (CRH) Somatostatin (SS; also GHIH, growth factor-inhibiting hormone) Dopamine (DA) Pineal Gland produces Melatonin Endocrine glands and the hormones secreted
The pineal gland is a reddish-gray body about the size of a pea (8 mm in humans), located just rostro-dorsal to the superior colliculus and behind and beneath the stria medullaris, between the laterally positioned thalamic bodies. It is part of the epithalamus. Pineal gland
The pituitary gland, or hypophysis, is an endocrine gland about the size of a pea that sits in a small, bony cavity (sella turcica) at the base of the brain. The pituitary gland secretes hormones regulating homeostasis, including trophic hormones that stimulate other endocrine glands. It is functionally connected to the hypothalamus by the median eminence. Pituitary gland
The anterior pituitary produces and secretes: growth hormone prolactin follicle-stimulating hormone luteinizing hormone thyroid-stimulating hormone adrenocorticotropic hormone endorphins and other hormones It does this in response to releasing hormones produced by the hypothalamus. These travel to the anterior lobe by way of a special capillary system, called the hypothalamic-hypophyseal portal system. These hypothalamic signalling hormones include: TRH (thyrotropin-releasing hormone) CRH (corticotropin-releasing hormone) DA (dopamine, "prolactin inhibiting factor"/PIF) GnRH (gonadotropin-releasing hormone) GHRH (growth hormone releasing hormone) Anterior pituitary (Adenohypophysis)
In new born period • Concentrations of ACTH, CTG, and TSH • are high, later they decrease
Late school period • Concentrations of luteal and follicle-stimulating hormones increases
Hypofunction of the hypophysis • Causes pituitary nanism (dwarfism)
Hyperfunction of hypophysis –(hyperpituitarism) • Pituitary gigantism and acromegaly
Hypofunction of the adrenohypophysis • Hypophyseal cachexia, Simmonds disease
Prolactin Prolactin is a peptide hormone synthesised and secreted by lactotrope cells in the adenohypophysis (anterior pituitary gland). It is also produced in other tissues including the breast and the decidua. Pituitary prolactin secretion is regulated by neuroendocrine neurons in the hypothalamus, most importantly by neurosecretory dopamine neurons of the arcuate nucleus, which inhibit prolactin secretion.
Disease States Relative elevations In children with precocious puberty of pituitary or central origin, LH and FSH levels may be in the reproductive range and not at the low levels typically for their age. High LH levels Persistently high LH levels are indicative of situations where the normal restricting feedback from the gonad is absent, leading to an unrestricted pituitary production of both, LH and FSH. While this is typical in the menopause, it is abnormal in the reproductive years. There it may be a sign of: Premature menopause Gonadal dysgenesis, Turner syndrome Castration Swyer syndrome Certain forms of CAH Testicular failure
Deficient LH activity Diminished secretion of LH can result in failure of gonadal function (hypogonadism). This condition is typically manifest in males as failure in production of normal numbers of sperm. In females, amenorrhea is commonly observed. Conditions with very low FSH secretions are: Kallmann syndrome Hypothalamic suppression Hypopituitarism Eating disorder Hyperprolactinemia Gonadotropin deficiency
Growth hormone (GH or somatotropin) is a polypeptidehormone synthesised and secreted by the anterior pituitary gland which stimulates growth and cell reproduction in humans Growth hormone
Examination of hypophysis • 1. laboratory investigatios of the level of hypophysis hormones • 2.R-graphy of the cranial Turkish saddle • 3.CT of the brain
The thyroid (from the Greek word for "shield", after its shape) is one of the larger endocrine glands in the body. It is a double-lobed structure located in the neck and produces hormones, principally thyroxine (T4) and triiodothyronine (T3), that regulate the rate of metabolism and affect the growth and rate of function of many other systems in the body. The hormone calcitonin is also produced and controls calcium blood levels. Iodine is necessary for the production of both hormones. Hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid) are the most common problems of the thyroid gland. Thyroid
The thymus plays an important role in the development of the immune system in early life, and its cells form a part of the body's normal immune system. It is most active before puberty. Thymus
Immature thymocytes undergo a process of selection, based on the specificity of their T cell receptors. This involves selection of T cells that are functional (positive selection), and elimination of T cells that are autoreactive (negative selection). Cells that pass both levels of selection are released into the bloodstream to perform vital immune functions.
The pancreas is an organ in the digestive and endocrine system that serves two major functions: exocrine (producing pancreatic juice containing digestiveenzymes) and endocrine (producing several important hormones, including insulin). Pancreas
1: Head of pancreas2: Uncinate process of pancreas3: Pancreatic notch4: Body of pancreas5: Anterior surface of pancreas6: Inferior surface of pancreas7: Superior margin of pancreas8: Anterior margin of pancreas9: Inferior margin of pancreas10: Omental tuber11: Tail of pancreas12: Duodenum Pancreas
beta cells-Insulin and Amylin alpha cells-Glucagon Deltacells-Somatostatin PP cells-Pancreatic polypeptide 50-80%lower blood sugar 15-20%raise blood sugar 3-10%inhibit endocrine pancreas 1%inhibit exocrine pancreas There are four main types of cells in the islets of Langerhans.
The structure of insulin. The left-hand side is a space-filling model of the insulin monomer, believed to be biologically active. Carbon is green, hydrogen white, oxygen red, and nitrogen blue. On the right-hand side is a cartoon of the hexamer, believed to be the stored form. A monomer unit is highlighted with the A chain in blue and the B chain in cyan. Yellow denotes disulfide bonds, and magenta spheres are zinc ions. Insulin
Computer-generated image of insulin hexamers highlighting the threefold symmetry, the zinc ions holding it together, and the histidine residues involved in zinc binding. Insulin
", as it is produced in the Islets of Langerhans in the pancreas) is a polypeptidehormone that regulates carbohydrate metabolism. Apart from being the primary effector in carbohydratehomeostasis, it has effects on fat metabolism and it can change the liver's ability to release fat stores. Insulin's concentration has extremely widespread effects throughout the body. Insulin (from Latininsula, "island
The World Health Organization • recognizes three main forms of diabetes: type 1, • type 2 and • gestational diabetes (or type 3, occurring during pregnancy)[1], • although these three "types" of diabetes are more accurately considered patterns of pancreatic failure rather than single diseases.
Thyroid \\ crisis\\ • 1.AN ACUTE ONSET OF HYPERTHERMIA, • 2.TACHYCARDIA • 3.RESTLESSNESS
Laboratory investigation • Newborns screening for T4 • TSH • X-ray delayed bone development • ECG depressed P and T waves and QRS complex,low voltage
Hyperthyroidism • Appear in the school period • 1.Emotional lability • 2.tremor • 3.increased appetite • 4.loss of body weight • 5.exophthalmos • 6.eyelid leg • 7.sweating and tachycardia
Laboratory investigation • T4 and T3 elevated • X-ray of bones: osteoporosis and bones resorption
hypoparathyroidism • Muscle pains, • Cramps, • Numbness, tingling and convulsions • The teeth are soft and erupt late • Dry and scaly skin • Cataracts may occurs
Laboratory findings • 1.low calcium • 2.elevatedphosphorus, • 3.low vitamin D, • 4,Low PTH • X-ray ;increased metaphyseal thickening • ECG:prolonged QT interval
Glucocorticoids function • Affect tissue metabolism • Increase protein and glucogen content in the liver • Influence the immune and nervous systems
Adrenal medulla secretes • Catecholamines: • dopamine, • norepinephrine epinephrine
Etiology: Adrenocortical tumor, ACTH-dependent bilateral hyperplasia Pituitary adenoma Abnormal production of ACTH Clinical manifestation: Moon face, a double chin, a buffalo hump, obesity, masculinization, hypertrichosis on the face and trunk, acne, clitoral enlargement, impaired growth and hypertension. Cushing s syndrome
Cortisol excess. • Cortisol excess as a result of organic causes or of prolonged cortisone therapy also has an adverse effect on growth in children.