Pituitary gland

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Pituitary gland or hypophysis is a small endocrine gland ,situated in a depression called ‘sella turcica’connected with the hypothalamus by the pituitary stalk or hypophyseal stalk. 

• Pituitary gland is divided into two division 

a. anterior pituitary or adenohypophysis 

b.  posterior pituitary or neurohypophysis. 

• Hypothalamo-hypophyseal relationship : hormones are secreted by hypothalamus and are transported to anterior pituitary through hypothalamo-hypophyseal blood vessels and posterior pituitary by nerve fibre of hypothalamo-hypophyseal tarct. 

• Anterior pituitary is ectodermal in origin and arises from the pharyngeal epithelium as an upward growth known as Rathke pouch.

Posterior pituitary is neuroectodermal in origin and arises from hypothalamus as a downward diverticulum

• Anterior pituitary has two types of cell, a. Chromophobe cells , b. Chromophil cells(alpha and beta cells).

• Posterior pituitary is made of neural type of cells called pituicytes  and unmyelinated nerve fibers. 

• Anterior pituitary secrete 6 hormones:

i. Growth hormone (GH) or somatotropic hormone (STH)

ii. Thyroid-stimulating hormone (TSH) or thyrotropic hormone

iii. Adrenocorticotropic hormone (ACTH)

iv. Follicle-stimulating hormone (FSH)

v. Luteinizing hormone (LH) in females or interstitialcell-stimulating hormone (ICSH) in males

vi. Prolactin

• Posterior pituitary hormones are

i. Antidiuretic hormone (ADH) or vasopressin 

ii. Oxytocin. 

• HYPERACTIVITY OF ANTERIOR PITUITARY

i. Gigantism

ii. Acromegaly

iii. Cushing Disease

• HYPOACTIVITY OF ANTERIOR PITUITARY

i. Dwarfism

ii. Acromicria

iii. Simmond Disease

• HYPERACTIVITY OF POSTERIOR PITUITARY

i. Syndrome of Inappropriate Hypersecretion of Antidiuretic Hormone (SIADH)

• HYPOACTIVITY OF POSTERIOR PITUITARY

i. Diabetes Insipidus


Written by: RB Sah (MBBS)

Reference: K. Sembulimgan Physiology Book; Guyton and Hall Medical physiology 


Location: Kathmandu 44600, Nepal

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