Pineal, Thyroid, Parathyroid Histology Flashcards
Cell type prominent in pineal gland
penealcytes
Function of pinealocytes
melatonin production/excretion in dark cycles
Pineal gland is organized into
lobules
Pineal gland and radiology
calcifies with age
acts as radiological marker
Melatonin functions
promotes sleep-wake cycles
suppresses gonadotropin
tumor => early onset puberty
Early onset puberty may be caused by
pineal gland tumor
decreases melatonin production
decreased inhibition of gonadotropin
increased levels of gonadotropin
Capillaries in thyroid
fenestrated capillaries
Colloid
stores thyroglobulin in follicular cells of thyroid
Precursor to thyroid hormones
thyroglobulin
stored in follicular cells
Function of thyroid parafollicular cells
neuroendocrine
secrete calcitonin**
What synthesizes thyroid hormones
follicles
Resting and active follicle states
resting: produce basal level of thyroid hormone
active: producing increased levels compared to baseline
Iodine is added to these residues of thyroid hormones
tyrosine residues
Iododination of thyroid hormone occurs where
extracellular of follicles in thyroid
Parathyroid chief/principle cells function
secrete PTH
