Flashcards in Wk1 Pineal, Thyroid, Parathyroid Histo Deck (19)
95% of the cells making up pineal gland:
What do pinealocytes do?
make melatonin at night
What is "brain sand" and what is its significance?
Ca and P buildup in pineal gland
radiological marker for small pineal gland
Nerve supply and NT released on pinealocytes:
superior cervical ganglion SNS fibers
Melatonin effects on hypothalamus:
suppress gonadotropins (FSH, LH)
**pineal tumors cause precocious puberty
**possibly contributes to seasonal affective disorder
Two thyroid cell types:
follicular -- surround colloid
Thyroid hormone precursor found in colloid:
Where are thyroid hormones synthesized?
active vs resting follicular cells
Role of parafollicular cells?
3 roles of calcitonin:
1. lowers blood Ca by decreasing bone resorption
2. decreases osteoclast motility and number
3. promotes Ca and PO4 excretion by kidney
Where does iodination of thyroglobulin occur?
Nice summary on slide...
Embryological origin of C-cells:
Embryological origin of parathyroid glands:
3 cell types in parathyroid gland:
1. Chief (principal) cells
3. Fat cells
Cells that produce parathyroid hormone (PTH):
Role of PTH:
1. stimulates osteoBlasts which in turn produce RANKL to stimulate osteoClasts (no PTH receptor)
--> bone resorption --> increased blood Ca