L25 Endocrine System Flashcards
Where is ADH produced?
Hypothalamus, and is released from posterior pituitary
Where is oxytocin produced?
Hypothalamus, and is released from posterior pituitary
Where is ACTH secreted?
Anterior pituitary
Where is melatonin secreted?
Pineal gland
Where is atrial natriuretic peptide secreted from?
Heart
Where is thyroid stimulating hormone released from?
Anterior pituitary
Where is adrenaline and noradrenaline released from?
Adrenal medulla
What hormones are secreted from the cortex of the adrenal glands?
Salt: mineralocorticoids (aldosterone)
Sugar: glucocorticoids (cortisol)
Sex: androgens
Where is calcitriol secreted?
Kidney
Where is calcitonin secreted?
Thyroid gland
What sections make up the anterior pituitary?
Pars tuberalis (layer of cells running up stalk)
Pars distalis (major portion of gland)
Pars intermedia (narrow band bordering posterior lobe)
(pars is Latin for ‘part’)
What structure encloses the pituitary gland?
Diaphragma sellae separates the pituitary gland and the sphenoid bone
How are the pituitary gland cell types classified according to staining pattern?
- Acidophils (acidic dyes)
- Basophils (basic dyes)
- Chromophobes (no cytoplasmic staining)
Which pituitary cell types are acidophils?
- Somatotrophs (growth hormone)
- Lactotrophs (prolactin)
Which pituitary cell types are basophils?
- Corticotrophs (ACTH)
- Gonadotrophs (FSH & LH)
- Thyrotrophs (TSH)
Why do chromophobes fail to stain?
Too few granules.
Why is the posterior pituitary also known as ‘pars nervosa’?
It is a continuation of the hypothalamus and contains hypothalamic neurons.
Which hormones are released by the posterior pituitary (pars nervosa)?
- ADH
- Oxytocin
What hormone is released from pars intermedia?
Melanocyte-stimulating hormone (MSH)
What hormones are released by the thyroid gland?
- Triiodothyronine (T3)
- Thyroxine (T4)
- Calcitonin
If the thyroid cells appear more flattened than cuboidal, and there is increased colloid present, what does this suggest about thyroid activity?
Underactive thyroid.
If the thyroid cells appear more columnar than cuboidal, and there is decreased colloid present, what does this suggest about thyroid activity?
Overactive thyroid
Which cells produce calcitonin?
C-cells in thyroid
What cells are present in the parathyroid glands?
- Chief cells (PTH)
- Oxyphils (unknown function; rare before puberty)
Why do glands need a good blood supply?
Their secretions need to get into circulation with ease
How are the secretory units of the pancreas arranged?
- Exocrine pancreas (99%) is arranged into clusters of tubulo-acinar glands
- Endocrine pancreas (1%) is arranged into small groups throughout pancreas called ‘Islets of Langerhans’
What do pancreatic alpha cells secrete?
Glucagon
Increases blood glucose by initiating breakdown of glycogen stored in the liver.
What do pancreatic beta cells secrete?
Insulin
Decreases blood glucose by stimulating glucose uptake by hepatocytes and synthesis of glycogen.
What do pancreatic delta cells secrete?
Inhibiting peptide
Inhibits release of glucagon and insulin. Slows food absorption and enzyme secretion.
What do pancreatic F cells secrete?
Pancreatic polypeptide
Inhibits gallbladder contractions
Regulates production of some pancreatic enzymes
Which is the innermost layer of the adrenal gland?
Medulla
M is for medulla, M is for middle.
What are the zones found in the adrenal cortex?
Outer: zona glomerulus
Middle: zona fasciculata
Inner: zona reticularis
True or false: Most hormones decline with age; cortisol is an exception.
True
True or false: Hormone replacement therapy can slow aging
True, but is linked with cancer
