M7S2: The Pituitary Gland (Hypophysis)

Question 1

Location of pituitary gland

Answer 1

-inferior to hypothalamus and sits in a con cavity of the sphenoid bone in middle of skill
-physical connection between hypothalamus and pituitary gland allows for communication between nervous and endocrine systems

Question 2

Lobes of pituitary gland

Answer 2

-anterior (adenophypophysis) and posterior lobe (neurohypophysis)
-each lobe secrete unique hormones

Anterior lobe:
-composed of glandular (adeno) secretory cells that produce and release 7 stimulating hormones
1. Thyroid stimulating hormone (TSH)
-released from anterior pituitary
-acts on thyroid gland, causing it to release thyroid hormones
2. Prolactin (PRL)
-induces mammary glands of breast to produce milk
3. Adrenocorticotropic hormone (ACTH)
-released by anterior pituitary
-acts on adrenal glands, causing them to release hormones
4. Growth Hormones (GH)
-stimulates growth in all cells
5 + 6. Follicle stimulating hormone (FSH) and Luteinizing hormone (LH)
-both act on gonads
-stimulate secretion of estrogen and progesterone and maturation of oocytes in the ovaries
-stimulate secretion of testosterone and sperm production in testes
7. Melanocyte stimulating hormone (MSH)
-stimulates melanocytes in the skin to produce pigment

Posterior lobe (Neurophypophysis):
-made up of nervous tissue
-releases 2 hormones
-those 2 hormones produced in hypothalamus
1. Antidiuretic hormone (ADH)
-promote reabsorption of water at kidneys
2. Oxytocin
-promote uterine contractions during childbirth
-plays role in breastfeeding
*refer to goodnotes

Question 3

Pituitary gland histology

Answer 3

-anterior and posterior lobes differ
Anterior lobe = made up of glandular tissue
Posterior lobe = made up of nervous tissue

Anterior:
-made up of glandular acini (small saclike cavities) that arranged into small groups (acinar complex?) surrounded by connective tissue
-stains darker compared to posterior lobe

Posterior:
-composed of nervous and connective tissue (DOES NOT CONTAIN ACINI)
-stains lighter compared to anterior lobe
*refer to goodnotes