Endocrine Glands Part 2 Flashcards
(97 cards)
1
Q
describe the parathyroid glands
A
small endocrine glands associated with thyroid
2
Q
where are the parathyroid glands located
A
posterior surface of thyroid gland, one superior and one inferior
3
Q
what are the parathyroid glands embryologically derived from
A
third and fourth branchial (pharyngeal) pouches
4
Q
what do parathyroid glands secrete and what does it do
A
parathyroid hormone- regulates serum calcium and phosphate
5
Q
what are the reciprocal effects of calcitonin and PTH
A
PTH slowly increases serum calcium, calcitonin rapidly decreases serum calcium
6
Q
what are the 3 ways in which PTH increases serum calcium
A
-increases osteoclast activity (inhibits osteoblasts)
- increases renal tubular absorption of Ca in kidneys (and inhibits resorption of phosphate)
- increases calcium absorption from gut via Vit D
7
Q
what is PTH stimulated by
A
decrease in blood calcium
8
Q
what happens if parathyroid is damaged in surgery
A
hypoparathyroidism
9
Q
what is hyperparathyroidism
A
excesss PTH production
10
Q
what it the result of hyperparathyroidism
A
bony erosion and lysis
11
Q
what are the 2 types of secretory cells in the parathyroid gland
A
chief cells and oxyphil cells
12
Q
what cell is more abundant in the parathyroid gland
A
chief cells
13
Q
what do chief cells secrete
A
PTH
14
Q
what do oxyphils contain
A
large numbers of mitochondria
15
Q
what is the function of oxyphils
A
unknown function
16
Q
what happens to the parathyroid gland in older individuals
A
fatty infiltration
17
Q
where are the adrenal glands located
A
superior to the kidneys
18
Q
what are the adrenal glands covered by
A
thin CT capsule
19
Q
what is the embryological origin of the adrenal cortex
A
mesoderm
20
Q
what is the adrenal cortex regulated by
A
ACTH secreted by the anterior pituitary
21
Q
what does the adrenal cortex secrete
A
steroid hormones structurally similar to cholesterol precursor
22
Q
what are the 3 functional classes of adrenal hormones
A
-mineralocorticoids
- glucocorticoids
- sex hormones
23
Q
what is the most common mineralocorticoid
A
aldosterone
24
Q
what does aldosterone do
A
control electrolyte and fluid balance
25
what do mineralocorticoids do
-regulate Na and K levels via Na pumps especially in renal tubules
- regulate BP via JGA
26
what is the most common glucocorticoid
cortisol
27
what do glucocorticoids do
stimulate gluconeogenesis and glycogenolysis which increase blood glucose
- increase metabolism and breakdown of proteins, carbohydrates, and lipids
28
what do sex hormones do
supplement gonadal production
29
what are the 3 layers of the adrenal cortex from superficial to deep
zona glomerulosa, zons fasciculata, zona reticularis
30
what does the zona glomerulosa secrete
mineralocorticoids
31
what is the largest region in the adrenal cortex
zona glomerulosa
32
what cell is in the zona fasciculata
spongicytes
33
what does the zona fasciculata secrete
glucocorticoids and small amounts of androgens
34
what affect does cortisol have on the immune system
decreases immune response
35
what causes cortisol release
stress
36
what does the zona reticularis secrete
small quantities of andorgens and glucocorticoids
37
what is another term for hypoadrenocorticism
addison's disease
38
what happens in addison's disease
failure of the adrenal cortex to produce mineralo and glucocorticoids
39
what is addison's disease usually caused by
atrophy of the gland often caused by autoimmune disease
40
what is the result of decreased aldosterone
decreased ECF volume, hyponatremia, hyperkalemia, mild acidosis -> shock, death
-AKA Addisonian crisis
41
what is the result of decreased cortisol in glucose
decreased blood glucose
42
what is the treatment for addisons disease
exogenous administration of meralocorticoids and glucocorticoids
43
what is another term for hyperadrenocorticism
cushings disease
44
what is the name for primary hyperadrenocorticism? secondary?
primary- adrenal hyperadrenocorticism
secondary- pituitary hyperadrenocorticism "classical form"
45
what is primary hyperadrenocorticism caused by
general adrenal hyperplasia or functional tumor of adrenal cortex -> excess cortisol secretion
46
what is secondary hyperadrenocorticism caused by
increased ACTH from anterior pituitary or other cortisol producing tumor
47
what does increased ACTH secretion lead to
adrenal hyperplasia and excess cortisol secretion
48
what is the adrenal medulla embryologically derived from
neuroectoderm
49
what cells does the adrenal medulla contain
chromaffin cells
50
what are chromaffin cells
modified, post ganglionic neuronal cells with secretory function
51
what is the adrenal medulla controlled by
preganglionic, sympathetic nerve fibers
52
what do chromaffin cells secrete
catecholamines such as adrenaline and noradrenaline
53
what are catecholamines in the adrenal medulla stored in
dense core granules
54
what does catecholamine release have a systemic effect on
adrenergic receptors throughout the body - especially skeletal, cardiac, and smooth muscle
55
what do catecholamines work in concert with glucocorticoids to do
prepare body for fight or flight response
56
what does adrenaline promote in the liver
glycogenolysis for energy
57
what is adrenaline responsible for the production of and what are they
enkephalins- endogenous opiates responsible for pain relief
58
what is a pheochromocytoma
generally benign, functional tumor of chromaffin cells of adrenal medulla
59
what are the symptoms of pheochromocytoms due to
increased epinephrine and norepinephrine secretion
60
what are the symptoms of pheochromocytomas
hypertension, headache, cardiac arrhythmias, chest pain, anxiety, panic attacks, nausea
61
what is the treatment for pheochromocytomas
surgical removal of tumor
62
what does the bulk of the pancreas contain and what does it do
exocrine acini- secrete digestive products into the gut
63
where do endocrine cells migrate in development and what do they form
migrate from duct system and aggregate around capillaries of pancreas to form islets of langerhand
64
where are islets of langerhans located
distributed throughout exocrine pancreatic tissue
65
what are the 3 main types of islet cells
alpha, beta, and delta
66
what islet cells are most abundant to least
beta> alpha > delta
67
what do alpha cells secrete and what does it do
secrete glucagon, increases blood glucose, stimulates glucogenesis and glycogenolysis
68
what do beta cells secrete and what does it do
secrete insulin- decreases blood glucose and stimulates intracellular glycogen synthesis
69
what do delta cells secrete and what does it do
secretes somatostatin- inhibits both insulin and glucagon production
70
what do other miscellaneous cell types in the pancreas secrete
vasoactive intestinal peptide (VIP) and pancreatic polypeptide (PP)
71
what is diabetes characterized by
hyperglycemia and glucosuria
72
what happens in type 1 diabetes
decreased insulin production
73
what happens in type 2 diabetes
decreased number of insulin receptors or decreased responsiveness
74
where is the pineal gland/body located
anterodorsal to cerebullem
75
what does the pineal gland develop from
neuroectodeerm as evagination of posterior portion of third ventricle from roof of diencephalon
76
what does the pineal gland do
communicates with hypothalamus; acts as photoreceptor in lower vertebrates
77
how does the pineal gland act as a photoreceptor
translates light intensity and duration into endocrine activity- important in circadian rhythms and seasonal reproductive cycles
78
what hormones does the pineal gland secrete
melatonin and serotonin
79
what does melatonin do
stimulates melanopores, chromatophores -> change in color intensity with reproductive cycle
80
what does serotonin do
vasoconstrictor and neurotransmitter
81
what affect does melatonin have in mammals
anti-gonadal effect, decrease sex activity
82
how does melatonin affect other hormones
-decreased GNRH from hypothalamus
- decreased sex hormone secretion from gonads
83
what are the two main cell types in the pineal gland
pinealocytes and neuroglial cells
84
what are pinealocytes and what do they secrete
highly modified neurons
- secrete melatonin and serotonin
85
what are neuroglial cells
support cells such as astrocytes, microglial cells
86
what might the pineal gland also contain
corpora arenacea
87
what is corpora arenacea
calcified accretions of Ca and Mg phosphate in aging individuals, "brain sand"
88
how do you identify the parathyroid
contains pale staining chief cells with clusters of larger, brighter pink oxyphil cells scattered throughout
89
how do you identify adrenal gland
cortex contains three alternating bands of dark and light pink cells
- central medulla contains chromaffin cells
90
what does the GI and respiratory endocrine system look like
a variety of endocrine cells scattered in the mucosa of GI, respiratory tract and other organs
91
what do the cells of the GI and respiratory endocrine system do
secrete peptide and amine hormones such as gastrin, secretin, CCK, and serotonin with neurosecretory granules and hormone like activity
92
what are the cells of the GI and respiratory endocrine system called
APUD cells - amine precursor uptake and decarboxylation
93
how are APUD cells similar
similar ultrastructure and metabolic pathways, however not common ancestors because different embryological origins
94
what are most APUD cells embryologically derived from
neural crest- aka neuroendocrine cells
95
what are other APUD cells in the gut embryologically derived from
endoderm- enteroendocrine cells
96
what are the best known examples of APUD cells
chromaffin cells, thyroid C cells, and pancreatic islets
97
what do enteroendocrine cells in GI and respiratory tracts secrete
gastrin, CCK, VIP, substance P, serotonin and bombesin
