Histology - Endocrine System Flashcards
Egs of peptide hormones
Glycoproteins -> TSH, LH, FSH
Short polypeptides -> ADH, Oxytocin, Prolactin, GH
Egs of amino acid derived hormones
Tyrosine -> thyroid hormone, catecholamines (E,NE,dopamine)
Tryptophan -> melatonin
Egs of lipid derived hormones
Steroid -> androgens, estrogens, progestins, calcitriol, corticosteroids
Eicosanoids ->. Leukotrienes, prostaglandins
Routes of communication in endocrine system
Endocrine
Paracrine
Autocrine
Synaptic
Features of endocrine system
One gland many hormones
One hormone many glands
One hormone, many targets, many effects
One hormone different messenger type
How are islet cell types identified
Cell distribution
Immunohistochemistry/ flourescence
EM
Two vascular systems in the pancreas
Insuloacinar portal system
Acinar vascular system
How are islet cells regulated
- Neural - arteriole wall inner action regulates blood flow
- Paracrine secretions - alpha cells regulate insulin release. Somatostatin inhibits insulin and glucagon release.
- Autocrine - neoropeptide release that acts on same cell to release hormone (eg alpha cells release glutamate to stimulate glucagon release)
Alpha cells release
Glucagon
Beta cells release
Insulin
Delta cells release
Somatostatin and gastrin
F-cells release
Pancreatic polypeptide
When are D cells stimulated
After protein rich meal
What hypothalamic nuclei releases ADH
Supra optic nucleus
What hypothalamic nuclei release OXY
Para ventricular nucleus
How is the pituitary formed
Down growth of floor of diencephalon joins to Rathke’s pouch (up growth of ectodermal lining of future oral cavity)