Pituitary Adenoma

Question 1

What are the three parts of the pituitary gland and their embryologic origins?

Answer 1

Anterior lobe (adenohypophysis): from Rathke’s pouch
Posterior lobe (neurohypophysis): from the infundibulum of the hypothalamus
Intermediate lobe: very small, appears like thyroid follicles

Question 2

What is the function of the posterior pituitary and where are its hormones produced?

Answer 2

The posterior pituitary stores and releases hormones made in the hypothalamus: oxytocin and vasopressin (ADH).

Question 3

What are the three cell types in the anterior pituitary and their staining characteristics?

Answer 3

Acidophils: stain red
Basophils: stain blue
Chromophobes: do not take up stain

Question 4

Which hormones are secreted by acidophils and basophils in the anterior pituitary?

Answer 4

Acidophils: secrete growth hormone (GH) and prolactin
Basophils: secrete ACTH, TSH, FSH, and LH

Question 5

What clinical syndromes might result from functional tumors of acidophils and basophils?

Answer 5

Acidophil tumors: Gigantism or galactorrhea (due to GH or prolactin)
Basophil tumors: Hyperfunction of adrenal (Cushing’s) or thyroid (hyperthyroidism) due to ACTH or TSH