Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Block 3 > Week 5 > Flashcards

Week 5 Flashcards

1
Q

Describe the function of oxyphil cells

A
  • larger than principal cells distributed amongst chief cells in the parathyroid
  • has lots of mito
  • appear at puberty/increase with age
  • function unknown
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What is dexamethasone suppression test?

A
  • evaluation for cushings disease (excess cortisol)
  • give exogenous steriod (to suppress cortisol production) should reduce ATCH production
  • measure serum cortisol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the blood flow to the neurohypophysis?

A
  • superior hypophyseal artery
    • comes in a the infundibulum
    • creates primary capillary plexus in lower hypothalamus
    • secondary capillary plexus in anterior pituitary
  • inferior hypophyseal artery
    • posterior pituitary
  • both capillary plexuses create the hypophyseal portal system
  • hormones leave the neurohypophysis via the hypophsial vein to dural sinuses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the embryological origin of andenohypophysis?

A

Oral ectoderm

  • looks very cellular
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are chromopobes?

A
  • Hates color
  • degrandulated acidophils and basophils
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the properties of the glycoprotein family?

A
  • proteins included
    • thyroid stimulating hormone
    • lutenizing hormone
    • follicle stimulation hormone
  • common alpha subunit and an unique beta subunit
  • differing degrees of glycosylation determines half life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is panhypopituitarism?

A
  • under secretion of most pituitary hormones
  • Causes
    • pituitary tumors, thrombosis of pituitary blood vessels, trauma
  • Effect
    • lethargy (hypothyroidism)
    • weight gain (decrease fat mobiliztion, lack of adrenocotical and thyroid hormones)
    • loss of sexual function
  • Treatment: thyroxine, cortisol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the role of the endrocine system?

A
  • maintains homeostasis be regulating body functions by coordinating the cellular activity
  • regulate
    • Na/H20 balance, blood vol/pressure
    • Ca2+ and phosphate
    • energy balance
    • response to stress
    • reproduction, development, growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the organs of the endocrine system?

A
  • Hypothalamus
  • Pituitary gland
  • Thyroid Gland/parathyroid gland
  • Adrenal glands
  • Pancreas
  • Ovaries/testies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the properties osteoclast?

A
  • precursor in bone marrow in a depression called Howships lucanae
  • Responds to calcitonin
    • suppresses boen resorption by osteoclast to decrease Ca2+ levels
  • large, motile, multinucleated
    • contains lysosomal enzymes
    • produces procollagenase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the functions of oxytocin?

A
  • Milk ejection
    • contracts myoepithelial cells that surround mammary alveoli
  • Hastens delivery
    • promotes delivery of placenta
    • reduces bleed - contracts uterine SM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Luteinizing hormone (LH)

Target?

Major actions?

A
  • Target
    • ovary
    • Testis
  • Major action
    • Ovary
      • Graafian follicle: increase ovulation, formation of corpus luteum
      • corpus luteum: increase estrogen and progestrone synthesis
    • Testis: increase testosterone synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is growth hormone secretion regulated?

A
  • Growth hormone and Insulin like growth factors (IGFs)
    • inhibits growth hormone release hormone (GHRH)
    • stimulates growth hormone somatostatin hormone (GHIH)
    • inhibits GH synthesis and release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does folliculstellate cell do?

A
  • Makes the cellular stroma
    • cell type located andenohypopsis
  • similar to dendritic cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe thyroid Follicular cells

A
  • Origin: endoderm
  • Target for TSH
  • responsible for the prodcution of thyrobulin and release of T3 and T4
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the symptoms of a pituitary hormone insufficiency?

A
  • ACTH def - cortisol insufficiency
  • TSH defi. - hypothyroidism
  • Gondatrophin defi. - hypogonadism
  • GH deficiency - failure to thrive and short stature in children
  • ADH deficiency - polyuria and polydipsia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is hypothalamic disease?

A
  • disfunction of the hypothalamus causing problems with pitiuitary gland hormone secretion and its target organs
  • causes
    • damage from malnutrition
    • genetic disorders
    • radiation
    • surgery, head trauma, lesion, tumor
  • effects - disruptions in
    • body temp regulation
    • growth, weight,
    • Na and water balance
    • milk production
    • emotions, sleep cycles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the types of hormones?

A
  • steroid and thyroid hormone
  • Protein/Amino acid hormone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the causes of acromegaly?

A
  • GH hypersecretion in adulthood
  • Causes
    • pituitary tumor after adolescence
  • Effect
    • bones grow in thickness: head and spine
    • enlargement of hands and feet
    • elongation of ribs
    • enlarged tongue, liver, kidneys, heart
  • Treatment: somatostatin analongs, surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Thyroid stimulating hormone

Target?

Major actions?

A
  • Target
    • Thyroid gland
  • Major actions
    • increase synthesis and secretion of thyroid hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does EC cell do?

A
  • Secretin
    • acts locally to stimulate bicarbonate in pancreas
  • Motilin
    • increases gastric and intestinal motility
  • Substance P
    • NT properties
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do acidophils make?

A
  • GH (somatotroph)
  • Prolactin (mammotroph)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is blood supply to the andenohypophysis?

A
  • Superior hypophysial artery forms a primary capillary plexus
    • gives of the portal veins
  • hypothalamophypophysial portal system
    • portal veins create secondary capillary plexus in pars distalis
  • blood leaves hypophysial vein to dural sinuses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe negative feedback

A
  • product of the stimulus will reduce the initial stimulus
  • most common control of hormone release
  • protects against excess hormone production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is long loop negative feedback?

A
  • systemic hormone produced feeds back all the way to the hypothalamic-pituitary axis
  • tertiary endocrinopathy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the 3 zones of the of the adrenal cortex?

A
  • Zona glomerulosa
  • Zona fasciculate
  • Zona reticularis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the types of endocrine disorders?

A
  • hormone deficiency
    • autoimmune destruction
    • deficiency of precursor
  • hormone resistance
    • receptor mutations
    • functional
  • hormone excess
    • tumors/mutations
    • autoimmune activation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do somatomedins (IFGs) work?

A
  • made in liver and site of action (bone and tissues)
  • stimulates chondrocytes and osteoclasts
    • increase bone elongation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does PP cell do?

A
  • secretes pancreatic polypeptide
  • Stimulates
    • gastric chief cells
  • Inhibits
    • bile secretion
    • intestinal motility
    • pancreatic enzymes
    • bicarbonate secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Growth Hormone (GH)

Target?

Major Actions?

A
  • Target
    • most tissues
  • Major actions - increases
    • growth in stature and mass - organized addition of new tissue
    • IGF-I production
    • protein synthesis
    • fat utilization
    • decrease glucose utilization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the function of chromaffin cells?

A
  • release epinephrine (80%) and norepinephrine (20%)
  • store opioid peptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Properties of protein/amino acid hormones

A
  • mostly water soluble
  • bind to hormone in cell membrane
  • MOA: act via 2nd messengers like cAMP, cGMP, Ca2+, Na+
  • Majority of hormones
  • synthesized as ‘preprohormonnes”
    • require post-translational processing
  • Short half life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What inhibits growth hormone secretion?

A
  • Somatostatin
  • obesity
  • increase in blood glucose and FA
  • aging
  • IGFs
  • GH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the results of a pituitary gland tumor?

A
  • increased secretion of
    • prolactin (prolactinomas)
    • GH (somatrotrophic adenomas)
    • ACTH (corticotrophic adenomas)
  • Decreased secretion of
    • LH/FSH (gondadotrophic adenomas)
  • Thyrotrophic adenomas
    • rare usually large when diagnosed
  • visual impairment if tumor is compressing optic nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What causes syndrome of inappropriate ADH secretion (SIADH)?

A
  • Problem
    • inappropriate ADH secretion
    • increases water retention causes atria of heart to be stretched
    • increased ANF and decreased plasma renin activity
    • hyponatremia and decreased plasma osmolality
  • Causes
    • Ectopic: ADH secreted from lung cancer
    • Eutopic: stroke, infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the hormones that produced by the anterior pituitary gland and what are there targets?

A
  • Thyrotropin - thyroid gland
  • Growth hormone
  • Corticotropin
    • with ACH - increases blood glucose level
  • Follicle stimulating and luteinizing - testes/ovaries
  • Prolactin - mammary gland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is short loop feedback?

A
  • anterior piuitary hormone feeds back on the hypothalamus to inhibit secretion of hypothalamic releasing hormone
  • secondary endocrinopathy
29
Q

What is diurnal hormone variation?

A
  • hormone secretion determined by circadian rhythm
    • set by pacemaker in hypothalamus
  • 24 hour pattern
    • low hormone levels at night
    • Levels peak in waking hours then decline as day progresses
31
Q

What is the structural features of the thyroid?

A
  • Encapsulated
  • CT extends down from the surface and forms lobules
  • Structural unit: follicles
    • lined by epithelium surrounding a lumen fille dwith collodial material enclosed by basal lamina
32
Q

What is the dawn phenomenon?

A
  • wake up because the surge of hormones
  • hormones result in increase in blood glucose
    • body will respond by releasing insulin
33
Q

What is ultrashort loop feedback?

A
  • hypothalamic hormone inhibits its own secretion
  • tertiary endocrinopathy
34
Q

What are the two cell types in the thyroid?

A
  • Follicular cell
  • parafollicular (C cell)
34
Q

What is positive feedback?

A
  • original stimulus results in an increased stimulation for hormone release
  • important during childbirth and lactation
  • regulated by the presence or absence of stimulation
35
Q

What are the two cell types of the parathyroid gland?

A
  • Principal (chief) cells
  • Oxyphil cells
37
Q

What are the four types of cells in the adenohypophysis?

A
  • Acidophils
  • Basophils
  • Chromophobes
  • Folliculostellate
37
Q

What do basophils make?

A
  • FSH and LH (gonadotrophs)
  • TSH (thyrotroph)
  • ACTH (corticotroph)
37
Q

How is T3 and T4 made?

A
  • Iodine pump, pumps iodide above serum levels in the thyroid follicular cell and it diffuses into the lumen of the follicular cell
  • Thyroid peroidase and thyroglulin are exocytosized into lumen
    • Thyroid peroxidase activates iodide into iodine
    • 2 iodine link to each thyroglobulin
    • Thyroglobulin yields 4 molecules of T3 and T4
  • Idothyroglobulin reenters the cell to fuse with lysosome and proteolysis of the idothyroglobulin to form the final forms of T3 and T4
37
Q

What is the embryological origin of the parathyroid?

A

mesoderm

37
Q

Follicle Stimulating Hormone (FSH)

Target?

Major actions?

A
  • Target
    • Ovary
    • Testis
  • Major actions
    • Ovary - increase folliculogenesis and estrogen synthesis
    • Testis - sperm maturation
38
Q

What is the ACTH stimulation test?

A
  • useed to evaluate adrenal insufficiency
  • give exogenous ACTH (stimulates cortisol production)
  • measure serum cortisol
39
Q

What is the structure of the adrenal gland?

A
  • Encapsulated
  • Cortex
    • 3 zones
  • Medulla
    • Chromaffin cells
40
Q

What are the causes of Dwarfism?

A
  • Causes
    • congenital defect
    • pituitary tumor or trauma causing panhypopituitarism (decreased in all anterior pituitary hormones secretion)
  • Effect
    • slow and reduced growth
    • juvenile appearance
    • if panhypopituitarism will also have hypothyroidism, hypogonadism, and low glucocorticoids
  • treatment: human GH + thyroxine, cortisol
42
Q

What are the parts of the andenohypopysis?

A
  • Para tuberalis - connecting stalk to hypothalamus
  • Para distalis - anterior lobe
  • Para intermedia - part that touches neurohypophysis
43
Q

What stimulates growth hormone secretion?

A
  • Secretion stimulation
    • GHRH
    • Ghrelin
    • starvation, protein deficiency (chronic)
    • decrease in blood glucose and FA
    • exercise, excitement, trauma, estrogen and androgens, sleep
45
Q

What are Herring Bodies?

A
  • Swellings at the distal of hypothalmohypophysical axons
  • Storage for oxytocin and vasopressin
47
Q

Describe the neural innervation of the neurohypophysis

A
  • Two hormones and neurophysis (protein carrier) are synthesized in hypthalamus and sent down unmyelinated axons to neurohypophysis via hypothalamoneurohypophysial tract
  • Supraoptic nuclei
    • Antidiuretic hormone (vasopressin)
  • paraventricular nucleus
    • oxytocin
48
Q

Beta-lipotropin (Beta-LPH)

Target?

Major actions?

A
  • Target
    • fat
  • major actions
    • possibly increase fat mobilization
    • little activity in humans
50
Q

What occurs with enzyme 21 hydroxylase (CYP21A2) gene deficiency?

A
  • required for cortisol and aldosterone synthesis
  • results in adrenal insufficiency
51
Q

Prolactin (PRL)

Target?

Major actions?

A
  • Target
    • mammary glands
    • hyopthalamus
  • Major actions
    • mammary glands: increases milk secretion and growth of mammary glands
    • hypothalamus: decreases GnRH
51
Q

What is the function of Antidiuretic hormone (ADH)/vasopressin (AVP)?

A
  • secretion is in response to a decrease in plasma volume and increase in plasma osmolality
  • Function
    • reabsorption of water - targets collecting tubules
      • binding causes increase in cAMP and causes the insertion of aquaporin-2 into the luminal membrane
    • vascular SM contraction
      • binding causes IP3, DAG to increase intracellular Ca2+
52
Q

What are the properties of the growth/prolactin hormone family?

A
  • belong to same gene family
    • both are polypeptide hormones
54
Q

What are the cell types of the pineal gland?

A
  • pinalocytes
    • produces melatonin at night
    • serotonin during day
  • Neuroglial cells
    • brain sand
56
Q

Properties of cell surface receptors

A
  • ligand recognition domain
  • intregral protein with cyoplasmic effector domain
  • hormone initiates intracellular signaling cascade
58
Q

What are the hormone binding proteins?

A
  • Corticosteroid binding globulin (CBG)
  • Sex hormone binding glogulin (SHBG)
  • Thyrotropin binding globulin (TBG)
  • Albumin (non specific)
59
Q

How does growth hormon affect body organ growth?

A
  • increases the size and number of cells
  • causes specific differentiation of certian cell types
61
Q

What is the function of the principal (chief) cells?

A
  • release parathyroid hormone (PTH)
    • increases Ca2+ indirectly
    • binds to receptors on osteoblasts to release osteoclast stimulating factor
    • made in rER
  • Paler, smaller cell
  • slow longer term homeostatic action
61
Q

What is a pulsatile pattern of secretion?

A
  • hormone released in regular pulse
  • varies in amplitude and frequency
    • continuous release can limit hormone action through desensitization
63
Q

What are the parts of the neurohypophysis?

A
  • Infundibulum - connecting stalk
    • median eminence - superior port that is on either side of the hypothalamus
    • infundibular process - the actual stalk
  • Para nervosa - neural lobe
64
Q

Function of zona glomerulosa

A
  • secretes mineralcorticoids - mainly aldosterone
  • regulated by renin (angiotensin system and ACTH)
  • regenertative zone of adrenal cortex
66
Q

What does D-1 cell?

A
  • secretes VIP (vasoactive intestinal peptide)
  • makes sure that blood glucose doesnt go too low.
    • its releases glycogen
  • stimulates pancreatic exocrine secretion and gut motility
68
Q

What is open loop?

A
  • No feedback
  • refers to control of hormone secretion by CNS stimulation
  • regulated by depletion of hormone in absence of further CNS stimulation
  • Epi
70
Q

What is the embryological origin of the pineal gland?

A

neuroectoderm

71
Q

How is the adenohypophysis formed?

A
  • Floor of diencephalon and the roof of the mouth fuse together
    • Roof of mouth makes the Rathke’s Pouch then attaches the diencephalon
72
Q

How does GnRH regulate the release of LH?

A
  • GnRH is released in a pulsatile fashion which is critical for gonadatropin secretion
    • spike in GnRH release which causes a very fast releease of LH into the peripheral blood
74
Q

Function of zona fasciculate

A
  • Thick middle zone
  • form parallel cords seperated by sinusoids
  • cells contain lipid droplets so larger
  • secrete glucocorticoids (coricosterone and cortisol)
  • Controlled by ACTH
75
Q

What are the types of secretion?

A
  • Autocrine
  • Paracine
  • Endocrine
  • Synaptic secretion
76
Q

What is the blood supply of the adrenal gland?

A
  • superior and middle adrenal arteries create capsular plexus
    • supplies three zones with fenestrated cortical capillaries (sinusoids)
  • to medulla - duel blood supply
    • medullary artery from the inferior adrenal artery and bypasses the cortex and joins with branches from cortical capillaries to form medullary venous sinuses
  • duel blood supply required for synthesis of epinephrine and to inhibit axonal growth
    • PNMT that activates epi activated by cortisol
77
Q

Properties of steroid and thyroid horomones?

A
  • lipid soluble
    • Derived from enzymatic modication of cholesterol
  • Bound to a plasma transport protein (globulins) but not active till free
  • Diffuse through cell branes to intracellular receptors
    • some can bind to surface
  • MOA: Alther rate of gene transcription
79
Q

How are protein hormones synthesized?

A
  • ribosomes create a peptide chain called a preprohormone
    • after this point everything is post-translational modification
  • enzymes in the ER chop off the signal sequence to create an inactive prohormone
  • prohormone goes through Golgi
  • enzymes and the prohormone bud off in a vesicle
    • enzymes chop the prohormone into one or more active peptides
  • vesicle is exocytosized
  • hormone goes to it target
80
Q

How does growth hormone affect skeletal growth?

A
  • increases proliferation of epiphyseal cartilage
  • increase conversion of cartilage to new bone
    • increase length of long bones and skeleton - until epiphyses of long bones fuse with shafts
  • increase bone thickening (proliferation of periosteal osteoblasts)
  • increase bone remodeling
81
Q

What are the causes of gigantism?

A
  • GH hypersecretion during childhood
  • cause
    • hyperactivity of otherwise normal cells
    • pituitary tumor
  • effect
    • rapid growth of all tissues
    • hyperglycemia
  • treatment: somatostatin analogs, sugery
82
Q

Function of zona reticularis

A
  • Inner most layer
  • graveyard of cortex
  • secrete mainly weak androgenic steroids
  • controlled by ACTH
83
Q

What are the properties of Pro-opiomelanocortin (POMC) family?

A
  • polypeptide hormone products of POMC gene
  • cleavage of POMC by endopeptidases (prohormone convertases)
84
Q

Adrenocorticotripic Hormone (ACTH)

Target?

Major actions?

A
  • target
    • adrenal cortex (Zona fasciculata)
  • Major actions
    • increases synthesis and secretion of adrenal cortical steriods
85
Q

What is the embryological origin of neurohypophysis?

A

Neural ectoderm

86
Q

What is episodic hormone release?

A
  • response-stimulus coupling enables endocrine system to remain responsive to physiological demands
  • secretory episodes occur with different periodicity
87
Q

What is the cause of diabetes insipidus?

A
  • Problem
    • unable to conserve water due to decrease ADH synthesis or insensitibity to ADH at collecting ducts
  • Causes
    • trauma, tumors, infection
  • Principle symptoms
    • increases water loss from kidneys and triggers increase in thrist (polydipsia)
88
Q

How does a radioimmunoassay (RIA) work?

A
  • Mix a known amount of radio labeled hormone with antibody
  • add parients serum containing hromone to compete with the bound radio labeled hormone
  • percipitate antigen/antibody complex
    • measure radioactivity
  • Calculate patient hormone level based on radiation detected
89
Q

Types of regulation of hormone release

A
  • Hormonal
    • Tropic hormones
    • Feedback loops
  • neutrient/ion regulation
    • glucose
    • Ca2+
  • Neural
    • adrenal medulla releasing epi
90
Q

Properties of an intracellular (nuclear) receptor

A
  • Respond to steroid hormones, Vit D, and thyroid hormones
  • Can be intermediate with surface receptors
    • receptor can be unbound in the cytosol
  • Results in changes in transcription and gene expression
91
Q

How do you interpretate hormone levels?

A
  • normal levels vary according to age and gender
  • pattern of hormone release can be affected by
    • illness
    • nutrition
  • look for regulatory factors
92
Q

Describe the properties of parafollicular (C cell)

A
  • Origin: neural crest
  • located in clusters and doesnt extend to lumen
  • APUD cell, EC, part of DNES
  • produces calcitonin
  • Decreases Ca2+
    • targets osteoclasts by reducing ruffling, #
    • promotes Ca2+ excretion into the urine in the kidneys

Block 3 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions