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Transcript 
DEVELOPMENT &
STRUCTURE OF THE
PITUITARY GLAND
DR TATHEER ZAHRA
ASSISTANT PROFESSOR ANATOMY
PITUITARY GLAND/
HYPOPHYSIS CEREBRI
Nomenclature
Master gland
Size
Shape
Weight
Capsule
Location
Relations
ANTERIOR
POSTERIOR
SUPERIOR
INFERIOR
LATERAL
• Duramater
• Duramater
• Diaphragma
sellae
• Dural floor of
the fossa
• Duramater
• Sphenoidal air
sinuses
• Dorsum sallae
• Sphenoidal air
sinuses
• Basilar artery
• Pons
• Optic chiasma
• 3rd ventricle
• Intercavernous
sinus
• Body of
sphenoid
• Sphenoidal air
sinuses
• Cavernous sinus
NEUROVASCULAR SUPPLY
Venous drainage
Superior & inferior
hypophyseal veins
Cavernous sinus
Nerve supply ~ Postsynaptic fibers
of ANS (Vasomotor to Ant. Lobe),
Hypothalamic nuclei (Post. Lobe)
Several superior
hypophyseal
arteries
Inferior
hypophyseal artery
Primary capillary plexus
Secondary capillary plexus
Fenestrated capillaries
Sinusoidal
capillaries
CONNECTIONS OF THE HYPOTHALAMUS
WITH PITUITARY GLAND
HYPOTHALAMOHYPOPHYSEAL
TRACT
HYPOPHYSEAL
PORTAL SYSTEM
DEVELOPMENT OF THE
PITUITARY GLAND
ADENOHYPOPHYSIS
• ECTODERM OF THE STOMODEUM
OROPHARYNX/ RATHKE’S POUCH
NEUROHYPOPHYSIS
• NEUROECTODERM OF THE FLOOR OF
THE 3RD VENTRICLE/ DIENCEPHALON
3RD WEEK
5TH WEEK
6TH WEEK
HYPOPHYSEAL DEFECTS
Pharyngeal Hypophysis
Craniopharyngiomas
Basipharyngeal Canal
Microadenoma (< 1cm in diameter)
Macroadenoma (> 1cm in diameter)
Mechanical effects of tumors ~ Neurological defects, Bitemporal hemianopia (Tunnel
vision), Headache, Epistaxis, CSF Rhinorrhea, Hydrocephalus etc.
Treatment options ~ Medication, Surgery, Radiotherapy, Combination
SURGICAL APPROACHES
TRANS-SPHENOIDAL APPROACH (via
orbit or nasal septum)
CRANIOTOMY FOR SUB-FRONTAL
APPROACH
CRANIOTOMY FOR TRANSCAVERNOUS APPROACH
LE FORT MAXILLOTOMY
INTRAOPERATIVE MRI (IMRI)
TRANS-SPHENOIDAL
APPROACH
Through orbit: Via ethmoidal air cells
after raising the periosteum from the
medial wall of the orbit
Through nasal septum:
*By elevating the nasal mucosa from the
nasal septum & removing the septum (the
nasal cavity itself is not entered)
*Maxilla-premaxilla (Cottle) approach by
preserving the caudal end of the nasal
septum & the anterior nasal spine
CRANIOTOMY FOR
SUB-FRONTAL APPROACH
CRANIOTOMY FOR
TRANS-CAVERNOUS
APPROACH
Trans-cavernous Approach
LE FORT MAXILLOTOMY
INTRAOPERATIVE
MRI (IMRI)
Pre operative:
Polytomograms of sella
& sphenoid sinus
Bilateral carotid
angiography
CT scan
Pneumoencephalography
Intra-operative:
Operating microscope
Intra-operative x-ray
control with image
intensifier
ORGANIZATION
ADENOHYPOPHYSIS
(Glandular part)
Pars tuberalis
Pars distalis-pars
anterior
Pars intermedia
NEUROHYPOPHYSIS
(Nervous part)
Pars nervosa
Infundibulum
(Infundibular stem &
Median eminence)
ADENOHYPOPHYSIS
PARS
TUBERALIS
PARS
DISTALIS
PARS
INTERMEDIA
PARS DISTALIS
75% of the mass of the hypophysis
Highly vascular
Common stains allow recognition of 3 cell
types
Folliculostellate cells
Chromophobes ~ 50 %
2 types of chromophils
Acidophils ~ 35-40 %
Basophils ~ 10-15 %
ACIDOPHILS
50%
SOMATOTROPES/
GH CELLS
15-20%
MAMMOTROPES/
PRL CELLS
REGULATION OF SECRETION
SOMATOTROPES/
GH CELLS
MAMMOTROPES/ PRL
CELLS
HYPOTHALAMUS
VIP
GHRH
TRH
DOPAMINE
SOMATOTROPES
PROLACTIN
GH
BASOPHILS
10%
GONADOTROPES/
FSH & LH CELLS
5%
THYROTROPES/
TSH CELLS
15-20%
CORTICOTROPES/
ACTH CELLS
Pars distalis: Crystal scarlet, aniline blue
& Martius yellow
REGULATION OF SECRETION
GONADOTROPES/
FSH & LH CELLS
HYPOTHALAMUS
CORTICOTROPES
/ ACTH CELLS
HYPOTHALAMUS
THYROTROPES
/ TSH CELLS
HYPOTHALAMUS
CRH
GnRH
TRH
CORTICOTROPES
GONADOTOTROPES
THYROTROPES
POMC
FSH & LH
ACTH
TSH
PARS TUBERALIS
 Folliculostellate
cells
 Basophils
Corticotropes
Gonadotropes
PARS INTERMEDIA
 Folliculostellate
cells
 Chromophobes
 Basophils
 Corticotropes
Black arrow Rathke's Pouch
Blue arrow –
Adenohypophysis
Red arrow –
Neurohypophysis
SUMMARY OF SECRETORY CELLS OF ADENOHYPOPHYSIS
PRH
+
PIH
-
SUMMARY OF REGULATION OF SECRETION OF ADENOHYPOPHYSIS
NEOROHYPOPHYSIS
NEUROHYPOPHYSIS
INFUNDIBULUM/
NEURAL STALK
MEDIAL EMINENCE
PARS NERVOSA
STEM
INFUNDIBULUM/ PITUITARY
STALK
PARS NERVOSA
HERRING BODIES
E/M of Herring bodies of rat posterior lobe
HORMONES OF THE PARS
NERVOSA
VASSOPRESSIN BY
SUPRAOPTIC
NUCLEUS
OXYTOCIN BY
PARAVENTRICULAR
NUCLEUS
CONTROL OF SECRETION
FACTORS AFFECTING
SECRETION:
Hypertonicity Hypovolemia
a. Osmotic stimuli
b. Volume effect
c. Other stimuli:
Osmoreceptors
Baroreceptors
Pain
Nausea
Surgical stress
Drugs:Morphine
Hypothalamus
Nicotine
Barbiturate
Alcohol
Thirst
Opiate antagonist
REFERENCES
The Developing Human, Clinically Oriented Embryology, By KEITH L.
MOORE - Latest Edition
LANGMAN’S Embryology, By T.W.SADLER - Latest Edition
LAST’S Anatomy Regional & Applied, By CHUMMY S.
SINNATAMBY - Latest Edition
Clinically Oriented Anatomy, By KEITH L. MOORE - Latest Edition
Clinical Anatomy By Regions, By RICHARD S. SNELL - Latest Edition
Basic Histology Text & Atlas, By LUIZ CARLOS JUNQUEIRA &
JOSé CARNEIRO - Latest Edition
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