78. Hormones from the neurohypophysis

Question 1

Pituitary gland – morphology

Answer 1

• Pituitary gland (hypophysis) is located in the centre of the cranial cavity.
• Posterior lobe of pituitary gland (neurohypophysis) is actually an extension of the hypothalamus, whereas the anterior lobe of the pituitary gland (adenohypophysis, distal part) is an endocrine gland.
• It is connected to hypothalamus and upper cerebral structures by the pituitary stalk (infundibulum).

Question 2

Oxytocin

Answer 2

Oxytocin: stimulates the uterus, especially during late pregnancy and birth. During birth oxytocin helps keep the strength of the labour contractions. You can give oxytocin to “activate” labour. The production of oxytocin will also be stimulated by the breastfeeding of the baby.

Question 3

Vasopressin

Answer 3

Vasopressin: functions on the kidneys, helps regulate the loss of water by regulating the uptake of water from the urine. This will also help reduce the level of urine. Dehydration will be very stimulating for vasopressin, because of the huge need for water absorption and storage. If the vasopressin secretion were to be inhibited the amount of urine would be doubled almost 10times!