Histology of Endocrine Organs Flashcards
Most endocrine organs lack a lumenn (free surface) except for?
Thyroid gland
What are the hormones that the hypothalamus releases that stimulate or inhibit the release of other hormones form the anterior pituitary?
Tropic hormones
What structure is comprised of glandular epithelial cells controlled by neurohormones released from hypothalamus?
Anterior pituitary
What structure is comprised of axons that carry ADH and oxytocin for storage and release from hypothalamus along with support cells?
Posterior pituitary
What type of cell secretes growth hormones?
Somatotropic cells
What type of cell secretes TSH?
Thyrotropic cells
What type of cell secretes ACTH and MSH?
Corticotropic cells
What stimulates the adrenal cortex to secrete stress related hormones and mediate metabolism?
ACTH
What stimulates melanocytes to produce melanin?
MSH
What type of cell secretes FSH and LH that act on gonads?
Gonadotropic cells
What type of cell secretes prolactin that stimulates milk production?
Mammotropic cells
Somatotrophs and mammotrophs fall under what type of cell type?
Acidophils
Corticotrophs, thyrotrophs, and gonadotrophs fall under what type of cell type?
Basophils
What part of the anterior pituitary contains acidophils, basophils, chromophobes, and sinusoidal capillaries?
Pars Distalis
What part of the anterior pituitary is rudimentary in adults, contains small basophils and colloid filled follicles lined by cuboidal epithelium, and is frequently has a remnant of lumen of Rathke’s pouch?
Pars Intermedia
What part of the posterior pituitary is continuous with median eminence of the hypothalamus via infundibular stalk, stores and releases hormones, and consists of Herring bodies, pituicytes, and fenestrated capillaries?
Pars Nervosa
What are expanded axonal nerve terminals that store ADH and oxytocin?
Herring bodies
What hormone targets the kidney and regulates sodium/water retention?
ADH
What hormone targets uterine smooth muscle and stimulates lactation; induces birth and may be involved in sexual arousal?
Oxytocin
What structure has a role in growth, development, and circadian rhythms?
Pineal gland
What does the pineal gland synthesize?
Melatonin and serotonin
What gland consists of pinealocytes, neuroglia, and calcified granular material?
Pineal gland
What type of epithelium are the follicular cells in the thyroid gland?
Simple cuboidal to columnar
What are the follicular cells in the thyroid gland surrounded by?
Colloid
What does colloid contain?
Thyroglobulin
Thyroglobulin is the storage form of what thyroid hormones?
T3 and T4
What is the only gland to store hormone outside the cell?
Thyroid
Where do the parafollicular C cells reside?
Just outside the follicles
What do parafollicular C cells secrete when blood levels of calcium are high?
Calcitonin
What are the major targets of calcitonin?
Kidneys and bone to decrease calcium
What pathology is caused by abnormal Abs stimulating TSH receptors causing over secretion of T3 and T4?
The patient presents with elevated metabolism, sweating, rapid heart rate, weight loss, eyeballs may protrude and is more common in women.
Grave’s disease
What pathology is caused by insufficient T3 and T4 production and often an autoimmune disease causing follicle cell death?
Patient presents with low metabolic rate, weight gain, lethargy, chilliness, edema, and mental sluggish.
Hypothyroidism
What pathology causes thyroid enlargement most commonly due to iodine deficiency along with follicle cells keep producing thyroglobulin but cannot iodinate it to make TH?
Goiters
What gland is important for regulating serum calcium and phosphate levels?
Parathyroid glands
What gland consists of chief cells and oxyphil cells?
Parathyroid gland
What cell in the parathyroid gland releases PTH?
Chief (principle) cells
When do chief cells release PTH?
When blood concentration of calcium falls below normal
What are the major targets of PTH?
Kidney and bone to increase calcium
What layer of the adrenal cortex influences sodium and potassium levels?
Zona glomerulosa
What hormone is released from zona glomerulosa that targets kidney function and is secreted in response to low blood pressure or blood volume?
Aldosterone
What layer of the adrenal cortex influences glucose metabolism and immune system and released under the control of ACTH from the anterior pituitary?
Zona fasciculata
What is released mainly by the zona fasciculata and deals with stress while mediating glucose metabolism?
Cortisol
What layer of the adrenal cortex influences secondary sex characteristics?
Zona reticularis
Chromaffin cells can be found in what structure?
Adrenal medulla
When stimulated by the sympathetic division of the ANS what population of cells secretes epinephrine and norepinephrine?
Chromaffin cells
What suprarenal gland syndrome deals with hyposecretory disorder usually in both glucocorticoids and mineralocorticoids?
Patients present with low blood glucose and sodium levels, severe dehydration and low blood pressure along with fatigue and loss of appetite.
Addison’s disease
What suprarenal gland syndrome is due to hypersecretion of glucocorticoids because of either an ACTH secreting pituitary tumor or a tumor in adrenal cortex?
Patients present with moon face, buffalo hump, high serum glucose levels, protein loss in muscles, muscle weakness, and lethargy
Cushing’s syndrome
The exocrine portion makes up most of the pancreas, the exocrine cells are organized in structures called?
Pancreatic acini
The endocrine cells of the pancreas are organized into clusters called?
Pancreatic islets or islets of Langerhans
In the pancreas, what secretes glucagon when blood glucose levels drop and stimulates the release of glucose from liver glycogen stores?
Alpha cells
In the pancreas, what secretes insulin when blood glucose levels are elevated and promotes glycogen storage in liver and entry into cells?
Beta cells
In the pancreas, what secretes somatostatin slowing the release of insulin and glucagon thereby controlling the rate of nutrient entry into the bloodstream and cells?
Delta cells
In the pancreas, what secretes pancreatic polypeptide that inhibit the release of somatostatin?
F cells
What supplies each islet of Langerhans which forms a network of capillaries lined by fenestrated endothelial cells?
Insuloacinar portal system
What supplies the pancreatic acini?
Acinar vascular system
