Lecture 9 - Endocrine System Flashcards
Endocrine system
regulates metabolic activities in certain organs and tissues of the body
-produces slow and diffused effect via chemical substances called hormones
Endocrine composition
endocrine cells
- clusters of cells within certain organs of the body
- ductless, richly vascular glands
Endocrine cells
isolated in the epithelial lining of the difestive tract and in the respiratory system
Endocrine glands (list them 5)
pituitary pancreas suprarenal thyroid parathyroid
Pituitary gland
aka hypophysis
immediately adjacent to and partially attached to the brain
-gland that produces hormones responsible for regulating growth, reproduction and metabolism
-easily falls off when dissecting
Signals function of other endocrine
pituitary 2 subdivisions
develop from different embryologic sources
- adenohypophysis
- neurohypophysis
Adenohypophysis (development and divisions)
aka anterior pit. develops from an evagination of the oral ectoderm (Rathke’s pouch), which lines the primitive oral cavity. loses contact
AKA Pars distalis- (pars anterior) -most important part of anterior Pars interior Pars tuberalis (stalk)
neurohypophysis (development and divisons)
aka POSTERIOR pit. develops from a neural ectoderm as a down-growth of the Diecephalan.
Maintains attachment to diencephalon of brain
median eminence
infundibulum (stalk)
pars nervosa (another name for neurohypophysis)
Anterior Pituitary
produces own hormones in the pars distalis and secretes them
Posterior pituitary
does not make own hormone
Secretes hormones manufactured in the hypothalamus from pars nervosa
Pars nervosa
Posterior Pituitary
- stores hormones in Herring bodies
- secretes ADH, oxytocin - to stimulate contraction
Pars distalis cell types
Makes its own hormone (Anterior Pituitary)
H and E stain
acidophils - stain lighter
basophils
Pars nervosa PAS stain
secretory endings with PAS positive granules can be visualized
Pars distalis basophils (name the cells and what they release)
- thyrotropes - secrete thyroid-stim hormone (TSH)
- gonadotropes- secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
- corticotropes - secrete adrenocorticotropic hormone (ACTH)
Acidophils (name the cells and what they release)
lactotropes secrete prolactin
somatotropes - secrete growth hormone
Pancreas (what the endocrine part is called)
Also has exocrine function
Endocrine portion is call Islets of Langerhans
islets of langerhans
Has pale clusters on H and E stain label it in pic.
produce hormones which regulate carb metabolism
alpha cells
beta cells
delta cells
pancrease alpha cells
glucagon - glucose release
pancrease beta cells
insulin - glucose uptake
pancrease delta cells
somatostatin - inhibitory hormone of gastric secretion
Suprarenal (adrenal gland)( two layers)
on top of kidney
surrounded by a dense fibroelastic capsule of CT
- parenchyma of gland is divided into two histologgically different regions
- suprarenal (outer)cortex
-suprarenal (inner) medulla
Suprarenal cortex
produces corticosteroids which are synthesized from cholesterol
suprarenal medulla
functionally related to and regulated by sympathetic system
produces epinephrine and norepinephrine
Adrenal cortex (the three zones)
3 zones ( know how to identify them the order)
Zona glomerulosa
zona fasciculata
zona reticularis
