Endocrine System Flashcards
The _____ gland is attached to the hypothalamus by the infundibulum.
Pituitary
The pituitary gland is made of 2 portions: What are they and what are they derived from embryonically?
Glandular portion (adenohypophysis)=derived from ectoderm of primative oral cavity
Neural portion (neurohypophysis)=derived from neuroectoderm
The adenohypophysis (glandular) is divided into 3 “pars”:
pars distalis, pars tuberalis, pars intermedia
The neurohypophysis (neural) is divided into 2 parts:
pars nervosa and infundibulum
The anterior lobe of the pituitary is made of 2 “pars”:
pars distalis + pars tuberalis
The posterior lobe of the pituitary is made of 2 “pars”:
pars nervosa + pars intermedia
The pars ____ of the anterior pituitary produces hormones
distalis
The pars _____ of the posterior pituitary releases hormones made by the _____
nervosa
hypothalamus
Adenohypophysis secretion (A*): Peptide hormones produced by special neurons in _____ nuclei are released into the primary capillary _____ of the _____, and these stimulate or inhibit the release of hormones by cells in the ______ _____.
hypothalamus
plexus
infundibulum
anterior pituitary
A*: Hormones from the hypothalamus stimulate release of 5 things:
There is also a hormone to inhibit ____ release
thryotropin, gonadotropin, somatostatin, growth hormone, corticotropin
prolactin
The hypophysis is supplied by the superior and inferior _____ artery. The inferior arteries primarily supply the pars ____.
hypophyseal
nervosa
The superior hypophyseal arteries supply the ____ _____, the upper part of the _____, and the lower part of the _____ via connection to the inferior hypophyseal arteries.
median eminence
infundibulum
infundibulum
Arteries supplying the median eminence and infundibulum end in ____ _____
capillary plexuses
Hypophyseal _____ _____ drain the areas supplied by capillary plexuses.
portal veins
The pars distalis (PD) consists of different secretory cells within a connective tissue _____ with _____ capillaries
stroma
fenestrated
PD: _____ make of 50% of cells and stain poorly, appearing clear or white.
chromophobes
there are 3 types of chromophobes in the PD
The three types of chromophobes in the pars distalis are _____ ____ cells, ______ chromophils, and connective tissue/____ cells
undifferentiated nonsecretory (“possibly stem cells”)
degranulated (few granules)
follicular
PD: Follicular cells form a ____ network that supports ____ cells. Some may have _____ function
stromal
chromophil
phagocytic
The two types of secretory cells in the pars distalis are ____ and _____
chromophiles and chromophobes
PD: Chromophiles can be _____ or ______
basophilic, acidophilic
PD: Acidophils stain with _____ and ______ but not _____. They secrete _____ ______.
eosin, orange G
PAS
peptide hormones
PD: Acidophils are usually _____ than basophils
smaller
PD: _____ are acidophils that produce growth hormone (_______) under control of growth hormone releasing factor and inhibiting factor (_______)
somatotrophs
somatotropin
somatostatin
PD: _____ are acidophils that produce prolactin. Prolactin stimulates and maintains ______ and concentration of prolactin increases during this process.
Mammotrophs
lactation
PD: Mammatrophs are under control of _____-releasing factor and prolactin-inhibiting factor (_____)
thyrotropin (TRF)
dopamine
PD: Basophilic staining chromophiles stain with _____ and other basic dyes. They secrete ____ hormones and are PAS ____.
hematoxylin
glycoprotein
positive
PD: Basophils are usually larger than acidophils and have ____ granules
fewer
PD: Gonadotrophs are ______ that secrete 2 hormones: _____ and _____
basophils
follicle stimulating hormone (FSH) and luteinizing hormone (LH)
PD: FSH stimulates development of ovarian ____ and acts on ____ cells to stimulate production of androgen binding protein
follicles
sertoli cells
PD: LH stimulates _____ in ovarian follicles and the corpus luteum. It also controls rate of testosterone synthesis by _____ cells.
steroidogenesis
leydig
PD: Corticotrophs produce ______. This stimulates growth and steroid synthesis in the zona ____ and zona _____ of adrenals
adrenocorticotropin (ACTH)
fasciculata, reticularis
PD: Thryotrophs produce _____ (also called _____-_____ ______). This is under the control of _____.
thyrotropin aka thyroid stimulating hormone
TRF (thyrotropin releasing factors)
The pars nervosa (PN) consists of _____ axonal processes from cell bodies located in nuclei in the ______ and ______ (astrocyte-like glial cells that contain glial fibrillary acidic proteins).
non-myelinated
hypothalamus
pituicytes
PN: The neurons end in close proximity to a _____ _____ _____
fenestrated capillary network
PN: Axons have large, neurosecretory granule-fulled dilations near the axon terminal called _____ _____
herring bodies
PN: Hypothalamic neurons release ____ and _____ _____ (vasopressin) near the capillary plexus
oxytocin, antidiuretic hormone
PN: Oxytocin is produced primarily by __________ nucleus cells and secondarily by _____ nucleus cells.
para ventricular, supraoptic
PN: _____ stimulates milk ejection by mammary glands as well as _____ smooth muscle contraction during child birth
oxytocin
uterine
PN: Antidiuretic hormone is produced primarily by _____ nucleus cells and secondarily by ______ nucleus cells
supraoptic
para-ventricular
PN: Antidiuretic hormone stimulates water reabsorption by the ____ _____ _____ _____
renal medullary collecting ducts
PN: _____ is a binding/carrier protein that complexes with neurohypophyseal hormones for transport down axons
neurophysin
The pars intermedia contains _____ and ____ cells and ____cysts. These cysts are ____ epithelium lined cavities.
basophil, chromophobe
rathke’s
cuboidal
The ____ ____ is a highly vascular region that contains veins of the hypophyseal portal system. It contains mostly _____
pars tuberalis
gonadotropes
Name the 4 main basophils released by the adenohypophysis (shown in diagram page 4)
ACTH, TSH, FSH, LH
Name the 2 acidophils released by the adenophysis (diagram page)
growth hormone, prolactin
_____ is due to excess growth hormone
acromegaly
Prolactin secreting tumors can lead to ___ due to lack of ____
infertility, ovulation
What is the most common cause of hypopituitarism?
pituitary tumors (adenomas)
In ____ _____ _____, hormone-secreting cells of the anterior pituitary are destroyed, involving some or all of the hormones
primary (intrinsic) pituitary destruction
Poor ____ lobe function leads to failure of lactation, amenorrhea, poor thyroid function, and adrenal insufficiency
anterior
Poor ____ lobe function leads to diabetes insipidus, due to impairment of ____ ____ in distal renal tubuli. Also causes polyuria and polydipsia
posterior
water resorption
The pineal gland is covered by ___ matter. There is/is not a blood-brain barrier concerning this organ.
pia, is not
The pineal gland contains connective tissue septa called ____ that extend from the capsule and divide the gland into ____
trabeculae
lobules
The pineal gland consists of _____ and ____ cells (aka interstitial cells)
pinealocytes, glial
The major pinealocyte product is _____, which regulates the ____ cycle
melatonin, sleep
Pinealocytes are slightly _____ with irregular lobulated nuclei and distinct ______. Silver stained cells appear to have long _____ branches
basophilic
nucleoli
tortuous
Occasionally, ____ ____ (brain sand) is seen in the pineal gland. These are made of _____ phosphate or _____ carbonate granules, that are _____ in shape
corpora arenacea
calcium, calcium
lamellar
What is the innervation of the pineal gland? Where do the nerves arise?
post ganglionic sympathetic nerves that originated in the superior cervical ganglion
External _____ affects pineal gland function.
lighting
Sunlight causes signals from retinal neurons to be relayed to the pineal gland, _____ secretion of melatonin.
inhibiting
Pineal tumors may restrict CSF flow through the _____ __ ____, causing _____.
aqueduct of sylvius
hydrocephalous
The thyroid gland is derived from the ____ portion of the alimentary canal ______
cephalic
endoderm
The thyroid gland consists of __ lobes united by an ____
2, isthmus
Thryoid lobes are made of _____ lined by ____ ____ epithelium. In inactive portions of the gland, the epithelium can be “almost” ____ in appearance. When active, the cells are more ____
lobules, simple cuboidal
squamous
columnar
Follicles of the thryoid have _____ cells that secrete T3 and T4
principal
Principal cells may have vesicles that are _____ ____ ____
colloidal reabsorption droplets
Thryoid gland follicles are usually filled with an acidophilic staining ____. This contains _____ _____, which is the inactive storage form of thyroid hormones
colloid
glycoprotein thyroglobulin
The thyroid gland has extensive blood and lymphatic capillary network surround the follicles. The endothelial cells in the capillaries are _____
fenestrated
(Thryoid gland):
____ (__) cells are resposible for calcitonin secretion.
parafollicular (C cells)
Parafollicular cells are found as part of the ____ epithelium or as isolated structures between the ____ _____
follicular
thyroid follicles
Calcitonin ____ bone resorption by _____ osteoclast activity.
supresses, inhibiting
Elevated blood calcium levels ____ calcitonin secretion. Secretion is _____ when calcium concentration falls below normal.
stimulates
supressed
note-PTH is more important in regulating blood Ca
C cells are ____ than follicular cells. They stain poorly in humans and may appear ____ or ____
larger
clear, white
Thyroglobulin is synthesized and glycosylated in the ____ of the thyroid ____.
rER (also glycosylated in the Golgi)
follicle
Iodide is ____ transported into the cytosol across the basal plasma membrane of the thyroid follicle. It is ____ in the cytoplasm and then enters the ____ where it iodinates ____ residues on the thyroglobulin
actively
oxidized
colloid, tyrosine
TSH released from the ____ ____ binds to TSH receptors of ____ cells. The cells then endocytose colloid which then combines with _____.
anterior pituitary
follicular
lysosomes
Iodinated residues cleaved from ____, ____, and _____ are released into the cytosal and then at the plasma basal membrane
thyroglobulin, T3, T4
Thyroxine= T__. Triiodothyronin=T_.
4, 3
Thyroid hormone stimulates ____ of genes
transcription
Thyroid hormone causes a general ____ in cellular metabolism
increase
Thyroid hormones ____ carbohydrate metabolism, _____ synthesis of cholesterol+phospholipids+Triglycerides, and _____ synthesis of fatty acids
stimulates
decreases
increases
Excessive production of thyroid hormone leads to weight ____, ____ heart rate+metabolism+respiration+appetite.
loss, increased
____ production of thryoid hormones leads to muscle tremors, tiredness, and excessive menstrual bleeding
excess
Insufficient iodine uptake leads to ____ T3/T4 production, which leads to ____ TSH production, which leads to goiter (follicular ______).
decreased
increased
hyperplasia
Graves disease is a form of ______
hyperthyroidism
Graves disease is caused by thryoid hyperfunction due to immunological dysfunction that produces a circulating _____ that has effects similar to ____
immunoglobulin
TSH
_____ disease is due to autoimmune destruction of thyroid resulting in HYPOthyroidism
hashimoto’s
In hashimoto’s disease, ____ ____ autoantibodies are produced. The thyroid is infiltrated with _____ and ____ cells
thyroid peroxidase
lymphocytes, plasma
Thyroid cancer occurs 3-4x as often in ____ than ____.
women, men
Hypothyroidism often exhibits _____, which is a localized skin disorder that causes swelling
myxedema
____ glands are usually 4 small glands situated behind the thyroid gland. Each gland sits within a ____ ____ capsule. ____ extend from the capsule into the gland
parathyroid
connective tissue
septa
Parathyroid glands have 2 main types of cells:
principal/chief cells, oxyphil cells
Principal cells have irregular granules that contain ____ _____
parathyroid hormone (PTH)
Parathyroid hormone _____ calcium in the body by _____ the number and activity of osteoclasts.
increases
stimulating
PTH causes calcified bone matrix to be ____ and calcium is _____
reabsorbed, released
PTH causes enhanced reabsorption of calcium from kidney _____ tubules and increases phosphate _____
distal
excretion
PTH acts on the intestine to increase absorption of Ca from food by stimulating vitamin ___ synthesis, which stimulates synthesis of ____ binding protein in the intestine
D
calcium
Oxyphil cells are ____ than chief cells. They stain intensely with eosin due to large numbers of _____. These appear after ____.
larger
mitochondria
puberty
Hyperparathyroidism is caused by ____, ____, and mainly _____
hyperplasia, carcinoma, mainly adenoma
Hyperparathyroidism causes increased blood ____ and blood ____ is low. Bone ____ may develop, as well as rubbery deformed bones, kidney stones, pancreatitis, peptic ulcers, and hypertension.
calcium
phosphate
cysts
HYPOparathyroidism exhibits with decreased serum ____ and increased serum ____. It causes ____ (muscle spasms), muscle cramps, exaggerated reflexes, and jaw locks
calcium
phosphate
tetany
The suprarenal gland has 2 layers: cortex, which is derived from _____, and the medulla, which is derived from ____ ____
mesoderm
neural crest
The medulla consists of cells arranged in cords or clumps supported by a ____ ____ _____
reticular fiber network
Medullary parenchymal cells (_____ cells) have numerous secretory granules that contain _____ and ____
chromaffin
epinephrin, norepinephrine
Cells secreting epinephrine have _____ granules than those containing norepinephrine
smaller
_____ _____ nerve cells may also be seen in the medulla
sympathetic ganglion
The adrenal cortex consists of three layers or zones: from outer to inner–>
zona glomerulosa, fasiculata, reticularis
Cells of the zona glomerulosa secrete _______ such as ______. Synthesis is stimulated by ______ and _____
mineralcorticoids
aldosterone
angiotensinsin 2, ACTH
remember, zona glomerulosa=SALT
Cells of the zona fasiculata secrete ______ such as ____. These cells have ____ capillaries arranged longitudinally between columns of parenchymal cells
glucocorticoids
cortisol/corticosterone
sinusoidal
remember, zona fasiculata=SUGAR
Cells of the zona reticularis secrete _____ such as ____
gonadocorticoids DHEA (dehydroepiandrosterone)/androstenidone
remember, zona reticularis=SEX
An adrenal medulla tumor, or ______, causes _____ and transient elevations in blood pressure. It is the most common adrenal tumor in _____
pheochromocytoma
hyperglycemia
adults
A _____ is a common tumor in children and does not affect _____ ____.
neuroblastoma
blood pressure
____ ____ is due to excess secretion of cortisol. It causes a round _____ face, high blood sugar, diabetes mellitus, ammenorrhea, hirsutism, acne, and emotionally _____
cushing syndrome
moon
labile
_____ ____ is due to excess production of aldosterone. It cases excess ___ retention, which leads to _____ and _____
conn’s syndrome
water
hypertension, hypokalemia
_____ _____ is due to adrenocorticol insufficiency. It causes weakness, nasuea, weight loss, and elevated _____ levels, which causes _____.
addison’s disease
ACTH
hyperpigmentation
_____ _____ is acute corticol destruciton. ______ sepsis can also cause endotoxic shock
waterhouse-friderischen syndrome
meniogococcal
