HISTOLOGIC STRUCTURE
OF ENDOCRINE SYSTEM
DR. I WAYAN SUGIRITAMA,M.Kes
HISTOLOGY DEPARTMENT
MEDICAL FACULTY OF UDAYANA
UNIVERSITY
www.sugiritama.blogspot.com
sugiritama@gmail.com
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HORMONE : organic chemical that liberate by
endocrine cells into vascular system
TARGET ORGAN : tissue/organ on which the
hormones act
ENDOCRINE GLANDS : Contain cell that
produce hormone (Pituitary, Adrenal,
Thyroid, Parathyroid, Islet Langerhan,s, and
Pineal)
ENDOCRINE
GENERAL CHARACTERISTICS
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COMMONLY SAID THAT THEY HAVE
NO DUCTS
RICH SUPPLY OF BLOOD VESSELS
EACH GLAND SECRETE ONE/MORE
HORMONE  SPECIFIC EFFECT UPON
ANOTHER TISSUE/ORGAN
PITUTIARY/ HYPOPHYSIS GLAND
• Develop from different
embryonic :
– Adenohypophysis :
evagination oral ectoderm
– Neurohypophysis : neural
ectoderm
• Connected to the brain by
neural pathways
•
Hormone secretion controlled
by Hypothalamus
SUBDIVISION OF HYPOPHYSIS
• Adenohypophysis
(anterior pitutiary)
– Pars distalis (anterior)
– Pars intermedia
– Pars tuberalis
• Neurohypophysis
(posterior pitutiary)
– Median eminence
– Infundibulum
– Pars Nervosa
ADENOHYPOPHYSIS (Pars Distalis )
 Chromophils (have an affinity for
histological dyes)
 Acidhophil (granules stain
orange-red with eosin)
 Somatotrophs
somatotropin (GH)
 Mammotrophs Prolactin
 Basophil (granule stain blue
with basic dyes)
 CorticotrophsACTH
 ThyrothropsTSH
 GonadothropsLH and
FSH
 Chromophobes (do not
take up stain)
 Degranulated chromophils
ADENOHYPOPHYSIS(Pars Intermedia and Pars Tuberalis)
 PARS INTERMEDIA
 Between pars distalis-nervosa
 Cuboidal cell line, colloid
containing cysts (Rathke,s
cysts)
 Houses cord of basophils along
networl of capillaries POMC
α-MSH,corticotropin, βlipoprotein,and βendorphine
 PARS TUBERALIS
 Surround hypophyseal stalk
 Highly vascularized by arteries
and hypophseal portal system
along which longitudinal cords
of cuboidal-low columnar epith.
 Cells contain secretory granule
(FSH?, LH?)
HYPOTHALAMOHYPOPHYSEAL TRACT
 Unmyelinated axon (cell
bodies in supraoptic and
paraventricular nuclei of
hypothalamus), enter the
posterior pitutiary
terminate in vicinity of
capillaries
 Nuclei sythezise  ADH
and oxytocin, and also
neurohypophysin
NEUROHYPOPHYSIS
 Pars nervosa technically is not
endocrine gland
 Hypothalamohypophyseal tract
end in the pars nervosa and
store the neurosecretions that
are produce by cells bodies
(hypothalamus)
 Axon supported by pituicytes
(glial-like cell)
 Axon contain granule of
vasopressin or oxytocin
 Chrome-alum staining reveal
Herring bodies (accumulation
of neurosecretory granule)
HYPOPHYSIS=MASTER GLAND
ADRENAL GLAND
• Consist of two layer :
– Adrenal cortex
• From coelomic intermediate
mesoderm
– Adrenal medulla
• From neural crest modified
sympathetic postganglionic
neurons
Adrenal cortex
• Zona glomerulosa
– Columnar/pyramidal cells are
arranged in closely packed,
rounded or arched clusters
– Mineralocorticoids(aldosterone)
• Zona fasciculata
– Polyhedral cells arranged in straight
cords
– Glucocorticoids (cortisone &cortisol)
and androgens
• Zona reticularis
– Cells disposed in irregular cords
that form anatomozing network
– Glucocorticoids and androgens
ADRENAL MEDULLA
• Parenchymal : polyhedral
cells arranged in cords/
clumps and supported by
reticular fiber network
• >> capillary supply
• >> secretory granules
– epinephrine &
– norepinephrine
THYROID GLAND
 Thyroid follicle is the
structural and functional unit
 Connective tissue septa
derived from the capsule
invaded the parenchym
 Secrete T3 and T4
PARENCHYM OF THYROID GLAND
FOLLICULAR CELLS
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Range from squamous-low columnar
Numerous short villi that extend into
colloid
Round, ovoid nucleus,
Basophilic cytoplasm, rod-shape
mitochondria, supranuclear golgi
comp. numerous small vesicle
Hormone T4 and T3 stored in colloid,
which bound to Thyroglobulin
PARENCHYME CELL OF THYROID GLAND
PARAFOLLICULAR CELLS
• Pale staining, lie cluster among
the follicular cells
• 2-3 times larger than follicular
cells; 0,1% of epithelium
• Round nucleus, moderate RER,
elongated mithocondria, well
developed golgi compl. Small
dense granule
• Secrete calcitonin
SYNTHESIS OF THYROID HORMONE
PARATHYROIDS GLAND
• Parenchym : consist of chief
cells and oxyphill cells
• Cells form the cords or cluster
surrounded by reticular fiber
and rich capillary network
• Connective tissue in older adult
:>> adipose cells (up to 60%)
• Secrete PTH  calcium
metabolism
PARENCHYM OF PARATHYROID GLAND
• CHIEF CELLS
– Eosinophilic-staining
– Contain secretory granules (PTH)
– Juxtanuclear golgi complex,
elongated mitochondria and
abundant RER
• OXYPHIL CELLS
– More deeply stain with eosin
– Less numerous , appear in group
– More mitochondria, small golgi
app. And little RER
– The inactive phase of Chief cells
PINEAL GLAND
• Cone-shape midline projection
from roof of the diencephalons
• 5-8 mm X 3-5 mm (120 mg)
• Covered by pia mater 
capsule septaincomplete
lobules
• Parenchym composed by :
pinealocytes & interstitial cell
• Melatonine secretion are
influenced by light and dark
PARENCHYME OF PINEAL GLAND
• Pinealocytes
– Basophilic cells, with one. two
long processed
– Nucleus spherical
– Cytoplasm : SER, RER, small
golgi app., mitochondria and
small secretory granule
– Produce Melatonin and serotonin
• Interstitial cells
– Scattered trough pinealocytes
– Deeply staining, with long
processed
– Calcium and carbonate deposite
 CORPORA ARENACEA
(BRAIN SAND)  >> older
ISLET OF LANGERHANS
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Appear as rounded clusters of
cells within exocrine pancreatic
tissue
Each islet consists of lightly
stained polygonal/ rounded
cells arranged in cords
separated by network of
fenestrated blood capillaries
Four type cells (A, B, D and F)
The B cells have irregular
granules (insulin )
Type A cell  Glucagons