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NEUROENDOCRINE SYSTEM. Anna L. Kiss Department Anatomy , Histology and Embryology Semmelweis University Budapest 2018. AUTOCRINE. ENDOCRINE (hormones). PARACRINE. NEUROENDOCRINE (neurohormone). MECHANISM OF SIGNAL TRANSMISSION. neuron.
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NEUROENDOCRINE SYSTEM Anna L. Kiss DepartmentAnatomy, Histology and Embryology Semmelweis University Budapest 2018
AUTOCRINE ENDOCRINE (hormones) PARACRINE NEUROENDOCRINE (neurohormone) MECHANISM OF SIGNAL TRANSMISSION neuron ACCORDING TO THE PLACE OF EFFECT OF SECRETION
LOCALIZATION OF DIENCEPHALON CEREBRAL HEMISPHERE CEREBELLAR HEMISPHERE LOWER BRAIN STEM UPPER BRAIN STEM = DIENCEPHALON
SUPRAOPTICO-PARAVENTRICULO-HYPOPHYSEAL MAGNOCELLULAR SYSTEM • 2 hypothalamicnuclei: • supraoptic • paraventricular III. ventricle (posterior pituitary)
ADENOHYPOPHYSIS median eminence 1. PARS TUBERALIS 2. PARS INTERMEDIA (INTERMEDIATE LOBE) 3. PARS DISTALIS (ANTERIOR LOBE) median eminence pars tuberalis infundibular stem infundibular process pars intermedia pars distalis NEUROHYPOPHYSIS 4. MEDIAN EMINENCE 5. INFUNDIBULAR STEM 6. INFUNDIBULAR PROCESS
FUNCTION OF POSTERIOR PITUITARY HORMONES OXYTOCIN Contraction of uterinal smooth muscle (delivery) Contractionof the mammary smooth muscle (milk ejection) VASOPRESSIN (antidiuretic hormone, ADH) Vasoconstrictor, enhances the blood pressure Water absorption in the collective tubules of kidney
pituitary stalk portal vessels posterior pituitary (neurohypophysis) anterior pituitary (adenohypophysis) PORTAL CIRCULATION OF THE ANTERIOR PITUITARY Béla Halász, in: Handbook of Clinical Endocrinology and Metabolic Diseases
RELEASING HORMONES LHRH (luteinizing hormone-releasing hormone) TRH (thyreotrop hormone-releasing hormone) CRH (corticotrop hormone-releasing hormone) GRH (growth hormone-releasing hormone) INHIBITING HORMONES Somatostatin (growth hormone-inhibiting hormone) Dopamine (prolactin-inhibiting hormone)
HORMONES OF THE ANTERIOR LOBE Trop hormones: stimulatory the target organ is another endocrine gland LH (luteinizing hormone) FSH (follicle stimulating hormone) TSH (thyroid stimulating hormone) ACTH (adrenocorticotrop hormone) STH (somatotrop hormone) = GH (growth hormone) LTH (luteotrop hormone, prolactin) Interleukins, growth factors (folliculostellate cells)
STH: growth hormon: - acts on all cells of the body - stimulates the liver to produce and secrete insulun-like growth factor - results in body growth In the abcense of GH during development
Growth hormon, STH, somatotrop hormon overproduction GIGANTISM ACROMEGALY normal giant normal In adult
1. Pituitary-dependent endocrine organs Thyroid gland Adrenal gland Ovary or testis 2. Pituitary-independent endocrine organs Pineal body Parathyroid gland Islets of Langerhans Placenta Enteroendocrine cells CENTRAL ENDOCRINE ORGAN: PITUITARY GLAND PERIPHERAL ENDOCRINE ORGANS
FEED-BACK MECHANISM ultrashort feedback (neural) hypophyseotroph neurons ultrashort feedback (humoral) anterior lobe short feedback troph hormones long feedback Béla Halász,in: Handbook of Clinical Endocrinology and Metabolic Diseases
Thyroid gland LARYNX THYROID GLAND T
HISTOLOGY OF THE THYROID GLAND colloid in follicles sinus hematoxylin-eosin staining thyroxin production immunostaining for calcitonin in C-cells (depresses the calcium level of the blood)
absorption by endocytosis colloid follicular epithelium lysosome colloid (thyroglobulin) Thyroxin (T4) Triiodthyronin (T3) RER amino acids + iodine capillary MECHANISM OF THYROID HORMONE PRODUCTION SYNTHESIS iodine
Thyroid hormon (thyroxin): increases the metabolic rate has morphogenic effect
absence of thyroxin during fetal life overproduction of thyroxin in adult CRETENISM BASEDOW-DISEASE
capsule cortex medulla HISTOLOGY OF THE SUPRARENAL (ADRENAL) GLANDS hematoxylin-eosin staining
Zona reticularis Zona glomerulosa Zona fasciculata sexual steroids mineralocorticoids glucocorticoids hematoxylin-eosin staining ZONES OF THE CORTEX AND THEIR HORMONES
FUNCTION OF ADRENAL HORMONES CORTEX MINERALOCORTICOIDS (aldosteron) water and salt balance GLUCOCORTICOIDS (cortisol, corticosterone) carbohydrate metabolism enhancing the level of blood glucose SEXUAL STEROIDS
Pituitary-independentendocrineorgans Adrenal gland medulla: pituitary independent!!! EPINEPHRIN, NOREPINEPHRIN involved in defense reaction to stress works together with the sympathetic nervous system
ADRENAL GLAND: MEDULLA • Sympato-adrenalsystem • Venoussinusoids:muscularwall • Chromaffincells: adrenalin, noradrenalin • Ganglioncells
Pituitary-independentendocrineorgans Pineal body Parathyroid gland Islets of Langerhans Placenta Enteroendocrine cells
Α (α) cells: glucagon: increases the blood sugar level B (ß) cells: insulin: decreases the blood sugar level blood sugar level
LANGERHANS-ISLETS Prepared by György Sétáló Prepared by Mihály Petkó Insulin, glucagon, biologically active peptides
HISTOLOGY OF THE PARATHYROID GLANDS Chief cells Oxyphil cell Fat cell hematoxylin-eosin staining Chief cells produce parathormone (controls the concentration of calcium and phosphate ions of blood)
Parat hormon: (parathyroid gland) • increases the blood Ca2+ level (increased reabsorbtion at the large intestine+remove Ca2+ from the bone) • decreases the blood phosphate level (prventing the phosphate reabsorbtion in the kidney) Calcitonin: (parafollicular cells of the thyroid gland) • decreases the blood Ca2+ level • Increases the blood phosphate level
HISTOLOGY LOCALIZATION brain sand Pinealocytes hematoxylin-eosin staining PINEAL BODY LOCALIZATION AND HASTOLOGY Melatonin, serotonin