Endocrine Disorders Flashcards
Pituitary Gland
a small gland located on a stalk hanging from the base of the brain
AKA: “The Master Gland”
Primary function is to control other glands.
Produces many hormones.
Secretion is controlled by the hypothalamus in the base of the brain.
Anterior Pituitary Gland
The hypothalamus controls the release of hormones from the anterior pituitary gland by releasing inhibiting or stimulating hormones
Posterior Pituitary Gland
The hypothalamus controls the release of hormones from the posterior pituitary gland via neural pathways
Releases “effector” hormones
(cause an effect to occur)
Oxytocin (the natural form of Pitocin)
stimulates gravid uterus
causes “let down” of milk from the breast.
ADH
(vasopressin) causes the kidney to retain water/hemostasis
Anterior Pituitary produces:
thyroid-stimulating hormone (TSH) Adrenocorticotropin hormone (ACTH) Growth hormone (GH) follicle-stimulating hormone (FSH) luteinizing hormone (LH)
Anterior Pituitary patho
TSH stimulates the thyroid gland to release its hormones, thus metabolic rate
ACTH stimulates the adrenal cortex to release cortisol, aldosterone, & androgens
Growth hormone (GH)
Stimulates growth & cell reproduction
Maintains or increases Blood Glucose levels
glucose usage by muscles & adipose tissues in prolonged GH excess
Induces insulin resistance in peripheral tissues
consumption of fats as an energy source
FSH
♀: Stimulates ovarian follicle growth & ovulation
♂: Stimulates sperm production
LH
♀: Stimulates corpus luteum development, release of oocyte, and estrogen/progesterone production
♂: Stimulates secretion of testosterone; development of testes
The Thyroid Gland
Lies in the anterior neck just below the larynx.
Two lobes, located on either side of the trachea, connected by a narrow band of tissue called the isthmus.
thyroxine (T4) and triiodothyronine (T3)
Affect growth and maturation of tissues, cell metabolism, heat production, and oxygen consumption
CV function; GI function; Neuromuscular
Parathyroid Glands
small, pea-shaped glands, located in the neck near the thyroid
usually 4 - number can vary
regulate the level of calcium in the body
produce parathyroid hormone - level of calcium in blood
Hypocalcemia can result if parathyroids are removed or destroyed.
Islets of Langerhans
specialized tissues in which the endocrine function of the pancreas occurs
include 3 types of cells: alpha, beta, delta
each secretes an important hormone.
Adrenal Glands
2 small glands that sit atop both kidneys.
Each has 2 divisions, each with different functions.
Adrenal Medulla and Adrenal Cortex
Adrenal Medulla
the Adrenal Medulla secretes the catecholamine hormones norepinephrine and epinephrine
used for stress response
produce vasoconstriction
Adrenal Cortex
The Adrenal Cortex secretes 3 classes of hormones, all steroid hormones:
Glucocorticoids
Mineralocorticoids
Androgenic hormones (not part of this lecture)
Glucocorticoids
accounts for 95% of adrenal cortex hormone production
the level of glucose in the blood
Released in response to stress, injury, or serious infection - like the hormones from the adrenal medulla.
Cortisol
Mobilizes glucose
Stimulates gluconeogenesis
Formation of glucose from proteins in the liver
Promotes protein breakdown (for energy source)
Suppresses inflammation & the immune response
Maintains vascular tone, too much causes hyperglucemia