Histology of Endocrine Glands Flashcards
What are follicular cells
Squamous/low columnar Junctional complexes Rounded, Central nucleus Basally: RER Apically: Golgi, secretory granules, microvilli Secrete thyroglobulin
What are Parafollicular cells
Derived from neural crest
Synthesis + secrete calcitonin
What is the colloid
Gelatinous
Storage of secretory product
What is the parathyroid gland derived from
Pharyngeal pouches
What are chief cells
Small polygonal, rounded nuclei, pale staining
Secrete PTH
What are oxyphil cells
Abnormally shaped mitochondria
Larger than chief + paler staining
What are alpha, beta, delta and F cells in the endocrine part of the pancreas
Alpha cells = Glucagon. Usually at periphery
Beta cells = Insulin. Centrally located
Delta cells = somatostatin. Scattered
F Cells = Pancreatic polypeptide - pancreatic enzyme, intestinal motility. Head of pancrease
What does somatostain do
Inhibit release of other islet hormones
Inhibit release of GH/TSH in anterior pituitary
How does the autonomic nervous system influence regulation of glucose
Parasympathetic: Increase insulin + glucagon
Sympathetic: Increase glucagon, inhibit insulin
How do you identify Zona glomerulosa
Rounded/arched cords of columnar/pyrimidal cells
How do you identify Zona fasciculata
Long cords of large polyhedral cells
Densely filled with lipid droplets
How do you identify Zona reticularis
Smaller cells n irregular cords interwoven with capillaries
More heavily stained due to fewer lipid droplets
What cytoplasm does the adrenal cortex have
Acidophilic cytoplasm
How are the cells arranged in the adrenal medulla
Cells arranged in cords, supported by reticular fibres
A lot of capillaries between cords
Parasympathetic ganglion cells present
How do you identify chromaffin cells
Large, pale staining
Norepinephrine secreted by catecholamine cells is converted into epinephrine in these cels
What are the different zones in the anterior pituitary
Pars distalis = cords of epithelial cells.
Pars tuberalis = funnel shaped
Pars intermedia = thin zone of basophillic cells
What is the difference between acidophilic and basophilic
Both are staining methods. They stain for different types of cells
Acidophilic: Somatotropic, mammotropic
Basophilic: Gonadotropic, thyrotropic, corticotropic
How is secretion in anterior controlled
Hypothalamic releasing/inhibiting hormones produced by hypothalamic nuclei + stoed in axons, transported by capillaries to pars distalis
What are pituicytes
Highly branched glial cells
Storage and release of neurohypophyseal hormones
What are herring bodies
Contain neurohypophyseal hormones. Situated in pars nervosa
Nerve impulse trigger release of peptides to be taken up by capillaries
