Endocrine System Flashcards
Name some hormones released from the Anterior Pituitary gland.
Thyroid Stimulating Hormone, Growth Hormone, Adrenocorticotropic Hormone, Melanocyte Stimulating Hormone, Luteinizing Hormone, Follicle Stimulating Hormone and Prolactin
Name some hormones released from the Posterior Pituitary gland.
Anti-diuretic Hormone (Vasopressin) and Oxytocin
What does TSH do?
Stimulates the Thyroid gland to produce T4 (thyroxine), and in turn T3 (tri-iodothyronine).
What does GH do?
Stimulates release of IGF-1 from the liver and other cells, helps with protein synthesis and plays a role in carbohydrate and lipid metabolism in many tissues
What does ACTH do?
Stimulates the adrenal glands above the kidneys to produce cortisol which helps humans respond to stress.
What does LH do?
In men, LH stimulates the release of testosterone. In women, LH stimulates the release of progesterone, the release of an egg from the ovaries and controls ovulation.
What does FSH do?
In women, it stimulates pubertal maturation, helps control the menstrual cycle and stimulates growth of an egg. In men, it helps control the production of sperm.
What does ADH (Vasopressin) do?
- Binds to V2 receptors causing an increase in water permeability in the distal tubule which allows for water re-absorption
- Binds to V1 receptors which causes an increase in vasoconstriction
What does Oxytocin do?
Helps the uterine muscle to contract in order to expel infant during childbirth, promotes ejection of milk from mammary glands and influences social behaviours.
What does Prolactin do?
Enhances milk production and breast development in females
What are the differences between the Anterior and Posterior pituitary gland?
Posterior Pituitary - consists of nervous tissue and connects to the Hypothalamus via a neural pathway
Anterior Pituitary - consists of glandular epithelial tissue and connects to the Hypothalamus via a unique vascular link
What inhibits the release of Prolactin?
Dopamine
What inhibits TSH and GH?
Somatostatin (GHIH)
What does Somatostatin (GHIH) do?
Inhibits the release of GH, TSH, insulin and glucagon.
What is the name of the precursor molecule of ACTH?
Pro-opiomelanocortin (POMC)
What three things does pro-opiomelanocortin (POMC) break down into?
ACTH, Endorphin, MSH
How do non-steroidal hormones work in the body?
Non-steroid hormone binds to surface receptor on cell. This activates an intracellular signalling cascade via a coupled G-protein. cAMP is released in signalling pathway to be converted into ATP (ACTH, Calcitonin, Epinephrine, Glucagon, PTH, ADH).
How do steroid hormones work in the body?
As steroid hormones are lipid derivatives, they can freely pass through the cell membrane. After this, they can either bind to a receptor protein, or can form a hormone-receptor complex. This then causes a change in gene expression, which increases transcription of mRNA. This then leads to the synthesis of new proteins (Testosterone, Oestrogen, Progesterone, Aldosterone, Vitamin D).
