Download Endocrine system Hormones

Endocrine system
2009
Endocrine system
Hormones (products of the
endocrine glands) are released in the
blood or tissue fluid); they have
influence on organs and tissues that
are far from the site of production
Hypothalamo-hypophyseal system
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Nc. supraopticus and
paraventricularis in
hypothalamus –
oxytocin and
vasopresin (ADH)
They are released
in neurohypophysis
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Hypothalamus:
Liberines :
TRH,GnRH,GRH,CRH,
PRF
Statines:
somatostatin,dopamin
Influence on hormone
production in
adenohypophysis
Neurohypophysis
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Unmyelinized nerve
fibres – Herring
bodies - granules
contain vasopressin
(ADH) and oxytocin;
neurophysin
Pituicytes = glial cells
(lipofuscin) – glial
fibrillary acidic protein
Neurohypophysis
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Oxytocin –increases tonus and causes
contraction of the uterine smooth muscle and
myoepithelial cells in the ducts of mammary
gland
Vasopressin – ADH –increases resorption of
water in collecting ducts of kidney and causes
contraction of smooth muscles in small arteries –
increases the blood pressure
Neurohypophysis
Adenohypophysis
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Blood supply:
 Superior hypophysial artery – hypothalamus
and pituitary gland– portal system
 Inferior hypophysial artery - neurohypophysis
Anterior pituitary gland
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Chromofobes: undifferentiated – stem cells,
folicullar cells (supportive system)
Chromophils:
Acidophilic: prolactin, growth hormone (GH)
Bazophilic: ACTH (adrenocorticotropic hormone),
TSH (thyroid stimulating hormone),
gonadotropic: FSH (follicle-stimulating
hormone), LH (luteinizing hormone)
Anterior pituitary gland
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Growth hormone – acts by IGF 1
(somatomedin) producedin liver and tissue.
Function growth – bone, anabolic hormone
Prolaktin – growth of mammary gland,
secretion of milk
Hyperprelactinemie – infertilita, amenorhea and
galactorhea.
Pituitary
glandpars
intermedia
Pineal gland
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Pinealocytes- production of melatonin
Astrocytes – supportive cells
Function: reaction on light – rythmic secretory
activity (melatonin is produced in darkness)
Biological clock – regulation of circadian rythms
It modifies function of endocrine glands
Pineal gland
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Pinealocytes
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Astrocytes
Thyroid gland
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Follicles – colloid (thyroglobulin) – cubic cells follicular – thyroxine (T4) and tri-iodotyrosine
(T3)
Function: stimulation of oxidative
phosphorylation in mitochondria (resorption in
intestine, regulation of lipid metabolism,
growth, development of CNS)
Parafollicular cells– calcitonin –decrease of Ca
level in blood –storage into bone and release
into urine.
Thyroid gland
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Folicullar cells
C – Parafollicular
cells: production of
calcitonin: regulation
of Ca level in blood
Production of thyroxine
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Synthesis of thyroglobulin proteosynthesis
Uptake of iodide from blood – active
transport – iodine pump
Activation of iodide and its binding to
tyrosine in thyreoglobulin (in follicular
colloid)
Resorption of thyroglobulin and its
braking by lysosomes – secretion of T4
and T3
Parathyroid gland
Chief cells – production of parathyroid
hormone – regulation of Ca level in blood
– activates osteoclasts in bone –
antagonist of calcitonin
Oxyphilic cells (mitochondrias)
Parathyroid gland
Suprarenal
gland
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Cortex :
zona glomerulosa
zona fasciculata
zona reticularis
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Medulla
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Cortex of suprarenal gland
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Mineralocorticoids – aldosteron –regulates–
resorption of Na in kidney (stimulation by
angiotensinII)
Glucocorticoids – cortisol, corticosteron –
regulation of metabolism, immunity
(stimulation by ACTH)
Androgens – dehydroepiandrosteron – anabolic
activity
Suprarenal gland
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Medulla:
Epinephrin (80%)
Norepinephrin (20%)
Reaction to stress –
Increase of blood
pressure, frequency
of heart
Suprarenal gland - medulla
Pancreas
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Exocrine gland – enzymes
Endocrine gland – islets of Langerhans –
controls of glucose level in blood and
function of GIT
Pancreas
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A-cells –
glucagon
B-cells –
insulin
D-cells –
somatostatin
F-cells –
pankreatic
polypeptide
Islet of Langerhans - insulin
Islet of Langerhans – B cell
A and D cells
Islet of Langerhans - glucagon
Islet of Langerhans - somatostatin
DNES
(diffuse neuroendocrinne system)
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Regulation of resorption and motility (gastrin,
secretin, GIP, cholecystokinin, motilin, VIP,
serotonin, somatostatin, glucagon, substance P,
ghrelin)
Cell can reach surface or they cannot. Granules
are located closely to basal lamina and they are
excreted into the blood
Endocrine system
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Ovary: estrogens and progesteron
Testis: androgens
Placenta: HCG (human chorionic
gonadotropin), placental lactogen, estrogens
and progesteron
Heart – cardiomyocytes- atrial natriuretic
hormone
Kidney– juxtaglomerular apparatus – renin –
angiotensin
Thymus: thymosin alfa, thymopoetin, tymolin,
thymic humoral factor (stimulates proliferation
and differenciation of T lymfocytes)
Adipose tissue: leptin, estrogens