Primary Endocrine Organs Flashcards
Primary endocrine organs
Hypothalamus, Pituitary Gland (anterior and posterior), Pineal Gland, Thyroid gland, Parathyroid Glands, Adrenal Glands and Pancreas
Hypothalamus
Hormones of the anterior pituitary gland
Growth hormone, prolactin, thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone and luteinising hormone
Growth hormone
Prolactin
Tsh
ACTH
FSH
LH
Hormones of the posterior pituitary gland
Antidiuretuc hormone and oxytocin
Antidiuretuc hormone (ADH)
Targets kidneys, promotes water retention increasing blood volume; targets arterioles by stimulating construction which increases BP
Oxytocin (OXT)
Targets uterus, stimulates uterine contraction during labour; targets mammary glands, promotes milk ejection during breast feeding
Which hormone does the Pineal gland produce?
Produces melatonin
Which organs does melatonin target?
Hypothalamus, pancreas, thyroid, pituitary, adrenals and gonads
Principle action of melatonin
Major function is to regulate sleep-wake cycle
(low melatonin = wakefulness
high melatonin = sleep)
Other additional functions being identified e.g. inhibiting the reproductive system until sexual maturity
Which hormones does the Thryoid gland produce?
Thryoid hormone (thyroid follicles) and calcitonin (parafollicular cells)
Thryoid hormone target and action
General target. Principle actions include: regulating tissue growth and development, promoting carbohydrate oxidation and controlling production of catecholamines.
Calcitonin
Targets bike and kidneys.
Decreases blood calcium concentration by: increasing deposition in bone and promoting calcium excretion by kidnevs
Types of thyroid hormones
• Tetra-iodothyronine (thyroxine) (Ta);
contains four iodine atoms
• Triiodothyronine (T3);
contains three iodine atoms
Which hormone does the parathyroid glands produce and what is its target and principle action?
Parathyroid hormone. Targets bone and kidneys. Increases blood calcium concentration by:
stimulating breakdown of bone, increasing calcium reabsorption by the kidneys, increasing the synthesis of calcitriol by the kidneys
What is the relationship between Calcitonin and PTH?
They are antagonists
Which hormones does the adrenal glands produce?
Mineralocorticoids, glucocorticoids, androgens and catecholamines
Mineralocorticoids
(e.g. aldosterone)
Targets kidneys. Promotes sodium and water retention. Promotes loss of potassium and hydrogen ions in urine.
Glucocorticoids
(e.g. cortisone, cortisol)
General target. Increases blood glucose, HR and BP (in response to stress). Maintains basal cell metabolism. Suppresses the immune system.
Androgens
Targets gonads and regulates sex hormones.
Catecholamines (e.g. adrenaline, noradrenaline)
Target is general. Mediates flight-or-flight response (i.e. increases heart rate, blood pressure, vasodilation and blood glucose)
Which hormones are hormones of the adrenal cortex?
Mineralocorticoids, glucocorticoids and gonadocorticoids (androgens)
Cateholamines are hormones of..?
The adrenal medulla
Which hormones does the pancreas produce?
Insulin, glucagon, somatostatin and pancreatic polypeptide
Insulin
(beta cells)
Targets muscle, adipose tissue and liver.
Decreases blood glucose levels by stimulating uptake of glucose and promoting glycogen formation
Glucagon (alpha cells)
Targets liver. Increases blood glucose levels by stimulating glycogen breakdown, increasing gluconeogenesis and inhibiting glycogen formation.
Somatostatin (delta cells)
Targets pancreas and hypothalamus. Inhibits release of glucagon and insulin and regulates the pituitary gland.
Pancreatic polypeptide
(PP cells)
General target, regulates feelings of hunger and satiety
What is the relationship between insulin and glucagon?
They are antagonists
