Gross anatomy, histology and developmental anatomy of

pituitary glandDr. Laxman Khanal

Asst. Professor, Department of Anatomy

BPKIHS, Dharan

17-11-2016

Q. ‘Pituitary’ is named so because it was though thata. Its size is like that of peab. It secret mucus like secretion which released from nosec. It is located in sella tursicad. It is master endocrine gland

Q. What structure lies lateral to the pituitary?a. Optic chiasma b. Diaphragm sellaec. Cavernous sinus d. sphenoid bone

Q. Hormone ‘Vasopressin’ is synthesized in.a. Posterior pituitary b. Anterior pituitaryb. Hypothalamus d. Thalamus

Introduction

• The pituitary gland is a pea-shaped structure measuring about 0.5inch in diameter that lies in the hypophysial fossa of the sphenoidbone and attaches to the hypothalamus by a stalk, the infundibulum.

• For long time pituitary gland was regarded as master endocrine glanddue to its control over other gland, but we now know that pituitaryitself has master that is hypothalamus.

• Pituitary gland is also called as ‘hypophysis cerebri’.

(Hypo=under, physis= growth, cerebri=cerebrum)

• Lies in hypophyseal fossa of sphenoid bone• Covered by dural fold (diaphragm sellae)• Above connected with hypothalamus by infundibulum.

3rd ventricle

Hypothalamus

Pituitary stalk

Pituitary gland CS

3rd ventricle

Post lobe

Ant lobe

Infundibulum Neurohypophysis

1. Pars posterior2. Infundibulum3. Median eminence

Cleft of pituitary

Intermediate lobe

3rd ventricle

Neurohypophysis

1. Pars posterior2. Infundibulum3. Median eminence

Adenophypophysis

1. Pars tuberalis2. Pars intermedia3. Pars anterior

3rd ventricle

OC

Prosencephalon (Forebrain)

1. Diencephalon 2. Telencephalon

Primitive oral cavity(stomodeum)

Floor of diencephalon

Roof of stomodeum

Rathke’s pouch

Neuroectodermaldiverticulum

Infundibulum

Neurohypophysis

AdenohypophysisAnt pituitaryIntermediate pituitary

Development of pituitary gland

CraniopharyngiomaRemnants of Rathke’s pocuh

Primary capillary plexus

Secondary capillary plexus

Hypophysial Portal vein

Hypophysial vein

Superior and inferior hypophysial artery

Capillary plexus of posterior lobe

Hypophysial vein

Trabecular artery

1. GH2. TSH3. FSH & LH4. ACTH5. Prolactin

1. ADH2. Oxytocin

Hypothalamic nuclei secretingreleasing and inhibitinghormone to ant lobe ofpituitary.

Primary capillary plexusreceiving releasing &inhibiting hormone.

Ant pituitary cellsrespond to releasing orinhibiting factors andrelease its hormones.

1. GH2. TSH3. FSH & LH4. ACTH5. Prolactin

1. ADH2. Oxytocin

Hypothalamo-hypophysial tract (HHT)

PVSO

Herring bodies

1. Basophilic cells-10%2. Acidophilic cells-40%3. Chromphobes cells-50%

1. Somatotropes - GH2. Lactotropes - Prolactin3. Corticotropes - ACTH4. Gonadotropes - FSH & LH5. Thyrotropes - TSH

Acidophilic

Basophilic

1. Basophilic cells-10%2. Acidophilic cells-40%3. Chromphobes cells-50%

Pars anterior

• Pituicytes• Nerve fibers • Herring Bodies• Capillaries

Pars nervosa

ADH stored in posterior pituitaryV2 R

V2 R

More water retain in body.Volume of urine decreases.

HHT system

Diabetes insipidus

Central DI

Nephrogenic DI No ADH

ADH synthesized in hypothalamus

Cushing disease

Pituitary adenoma of ant lobe

High ACTH secretion

High cortisol from adrenal cortex

• High BP• High blood glucose level• Moon face• Fatigueness

Robert Wadlow (8 ft 11 inch)

Peter Dinklage (4 ft 5 inch)

Big show (200 kg)

• Gigantism • Acromegaly• Dwarfism

Pituitary disorders