Endocrine System Flashcards
What are prostaglandins made from?
The fatty acid arachidonate
Functions of prostaglandins
o Uterus – muscular contraction (period pains)
o Mediate effects of pyrogens (cause fevers)
o Memory & brain function.
o Increase blood flow in kidneys.
o Dilate small blood vessels – redness seen in inflammation.
o Protect stomach lining.
o Sensitise nerve endings that stimulate pain responses.
o Relax and contract lungs.
What are some growth factors produced in the body?
granulocyte & macrophage colony stimulating factor, platelet derived growth factor, epidermal growth factor, nerve growth factor.
What is leptin?
produced from adipose tissue – acts on hypothalamus to indicate satiety – obesity – genetic alteration of leptin – hypothalamic cells lack receptors.
What hormone is produced by the heart?
atrial natriuretic hormone – antagonistic of aldosterone
Describe the pineal gland?
brain – melatonin (regulates wake/sleep cycle)
Describe the thymus?
lobular & lies beneath sternum – converts lymphocytes into T lymphocytes – cells produce thymosin (aid in lymphocyte differentiation)
Describe the pancreas?
exocrine (digestive enzymes) & endocrine gland (insulin & glucagon - antagonistic)
What are the 2 parts of the adrenal glands?
adrenal medulla & adrenal cortex
Describe the adrenal glands?
sits above kidneys – hypothalamus controls.
Describe the adrenal medulla?
cells derived from peripheral nervous system – sympathetic division of the autonomic nervous system controls involuntary response & adrenal medulla – tropic hormones don’t trigger these cells – produces adrenaline (epinephrine) – heart rate quickens, increased chemical reactions, glucose released from liver.
Describe the adrenal cortex?
produces mineralocorticoids (regulate certain ions e.g. aldosterone), glucocorticoids (affect glucose metabolism – glucose broken down from non-carbohydrate substance), androgens (testosterone), progesterone, oestrogen
Describe the parathyroid gland?
parathyroid hormone (works with calcitonin) maintains optimum Ca levels – stimulates osteoclasts, kidneys to reabsorb Ca, intestinal cells to absorb Ca from food – antagonistic to CT
Describe the thyroid gland?
secretes T3 (triiodothyronine) & T4 (thyroxine) –controls metabolism – most body cells have receptors for thyroid hormones – cause effects of body – hyperthyroidism and hypothyroidism – calcitonin (decrease calcium levels)
What hormones are produced by the posterior pituitary?
Antidiuretic hormone & oxytocin
What is anti diuretic hormone?
control volume of blood – regulates water reabsorption in nephrons.
What is oxytocin?
females during pregnancy – binds to target cells in uterus - causes contractions
What hormones are described the anterior pituitary?
melanocyte stimulating hormone, prolactin, growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, gonadotropins (luteinising hormone and follicle stimulating hormone)
What is prolactin?
acts with oestrogen & progesterone to stimulate the mammary gland (produce breast milk)