Endocrinology Flashcards
What is the function of the pineal gland
Secretes melatonin and is involved in circadian rhythm regulation.
Where is the pineal gland located
In the centre of the brain, behind the thalamus
What 4 cells are in the pancreatic islets and what do they secrete.
Alpha - Glucagon
Beta - Insulin and Amylin
Delta - somatostatin
PP - Pancreatic poly peptide
glucagon principle action
promotes hepatic glycogen breakdown and gluconeogenesis
insulin principle action
promotes glucose uptake in cells, glycogenesis, lipogenesis, and protein synthesis
Somatostatin principle action in the pancreas
inhibits insulin and glucagon secretion
Amylin principle action
Helps control appetite and stomach emptying
Pancreatic polyeptide principle action
appetite regulation and digestion coordination.
- T3 is also known as
c) Triiodothyronine
Aldosterone (Mineralcorticoid)
where? control? action?
Adrenal cortex outer layer.
Controlled by RAA system.
Regulates blood pressure by influencing K+ excretion and Na+ retention.
Cortisol
(glucocorticoid)
where? control? action?
Adrenal Cortex middle layer.
Controlled by HPA axis > Adrenocorticotropic hormone (ACTH).
Helps the body manage and use carbohydrates, protein and fat. It also causes changes in metabolism to help the body manage stress, and it suppresses the immune system.
Adrenal Androgens and Oestrogen
where? control? action?
Adrenal Cortex inner layer.
Controlled by HPA axis > Adrenocorticotropic hormone (ACTH).
Responsible for male and female secondary sexual characteristics, oestrogen also stimulates ovulation.
Epinephrine (Adrenaline)
where? control? action?
Adrenal Medulla.
Sympathetic nervous system in response to stressful stimuli.
short-term stress. It increases your heart rate, blood pressure and blood sugar level.
Norepinephrine (noradrenaline)
where? control? action?
Adrenal Medulla.
Sympathetic nervous system in response to stressful stimuli.
Constricts blood vessels, increases your heart rate, blood pressure and blood sugar level.
principal action of parathyroid hormone
Regulates blood calcium levels
Action of Anti-diuretic hormone (ADH)
ADH acts on G-protein coupled receptors on cell membranes in distal convoluted tubules and collecting ducts, opening channels to allow water to move down an osmotic gradient from nephron back into blood stream conserving water.
Hormones of the Anterior pituitary
Growth Hormone, Luteinising Hormone, Follicle Stimulating Hormone, Adrenocorticotropic hormone, Thyroid Stimulating Hormone
Thyroid Stimulating Hormone action
Stimulates thyroid hormone production in the thyroid
Adrenocorticotropic hormone action
Stimulates the adrenal glands to produce cortisol and other hormones, and helps the body respond to stress
Growth Hormone action
Stimulates growth in children, and enhances lipolysis and fatty acid oxidation in adults
Luteinising Hormone action
Stimulates ovulation in women and testosterone production in men
Follicle-stimulating hormone (FSH) action
Stimulates the ovaries to produce eggs and estrogen, and the testes to produce sperm.
action of water soluble hormones
Water-soluble hormones bind to receptors on the plasma membrane of a cell, which causes a change in cell activity. This change in activity can then send feedback to the hormone-producing cell
Negative feedback hormone control
hormones are released to counteract a change in optimal homeostasis, low levels of a hormone stimulate production of that hormone. E.g low thyroid hormones stimulates TSH and increased TH production.
