6) Posterior Pituitary Hormones

What is the posterior pituitary also known as?

Neurohypophysis

What type of neurons make up the posterior pituitary?

Magnocellular neurons

What are Herring bodies primarily responsible for?

Storing hormones

What is the primary structural feature of capillaries near posterior pituitary axons?

Fenestrations

Which hormone is also known as vasopressin?

Antidiuretic hormone

Where are V2 receptors located?

Collecting ducts of the kidney

Which second messenger system is activated by ADH binding to V2 receptors?

cAMP/PKA pathway

What condition results from the inability to secrete ADH?

Diabetes insipidus

What distinguishes diabetes insipidus from diabetes mellitus?

Tasteless urine

What type of receptors does ADH bind to on blood vessels?

V1 receptors

What is the Ferguson reflex associated with?

Uterine contractions during labour

Which two molecules amplify uterine contraction during labour?

Oxytocin and prostaglandins

How is oxytocin release triggered during breastfeeding?

Through suckling at the nipple

What effect does oxytocin have on the mammary gland?

Contracts smooth muscle to release milk

Which two main peripheral actions are associated with oxytocin?

Uterine contraction and milk letdown

Which hypothalamic nucleus is involved in ADH secretion?

Paraventricular nucleus

When is ADH most likely to be secreted?

With increased plasma osmolarity

What best describes the mechanism of urine concentration involving ADH?

ADH inserts aquaporin-2 in the apical membrane