Pituitary gland

Pituitary gland is located within the sella turcica of the sphenoid bone.

Anterior and posterior pituitary lobe

Adenohypophysis	Neurohypophysis
75% of the gland Ectodermal origin from roof of the stomodeum Three components: Pars tuberalis includes Portion of the infundibular stalk Median eminence of hypothalamus Pars intermedia Pars distalis: majority of the gland, has no direct arterial supply	25% of the gland Diencephalic origin Three components: Pars nervosa (posterior lobe) Infundibulum Nuclei (supraoptic and paraventricular)

Hypophyseal portal system

Hypophyseal portal system is formed by the superior hypophyseal arteries (supraclinoid ICA) and the inferior hypophyseal arteries (branch of cavernous ICA meningohypophyseal trunk). These arteries join in and around the pituitary stalk and form sinusoids that feed the infundibulum and the anterior pituitary gland. The superior hypophyseal artery supplies the infundibulum and the median eminence. The inferior hypophyseal artery supplies the posterior pituitary lobe.