Brainscape's Knowledge GenomeTM

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


See full index

BMS200 > Endocrine > Flashcards

Endocrine Flashcards

1
Q

magnocellular neurons vs parvicallular neurons
size and location
hormones released from where?

A

magnocellular: larger, located within supraoptic paraventricular nuclei. hormones released from posterior pituitary

parvicellular: smaller, located within multiple different nuclei in hypothalamus
hormones released from median eminence (portal vein near ant. pituitary), brainstem, SC

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

which neurohormones are produced from magnocellular neurons

A

oxytocin
vasopressin/ADH

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

which neurohormones are produced from parvicellular neurons

A

CRH
TRH
GHRH
GHIH
DA
GnRH/LHRH
PRH

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

oxytocin function

A

stimulate uterine contractions

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

vasopressin/ADH function

A

promote water reabsorption
stimulate thirst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

CRH function

A

stimulates ACTH release from anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

TRH function

A

stimulates TSH release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

GHRH/LHRH function from anterior pituitary

A

stimulate FSH and LH release from anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does PRIH/DA do?

A

PRIH - prolactin inhibiting hormone
DA - domapine

function: inhibits prolactin release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where is the inferior hypophyseal artery

A

posterior pituitary, where the magnocellular neurons release their hormones into systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe the circulation of blood and hormones through the anterior pituitary

A
  • some cells can make their own hormones (lactotrophs, somatotrophs)
  • hypothalamic parvicellular neurons release hormones into primary capillary plexus within the median eminence -> superior hypophyseal artery -> primary capillary tract -> portal vein -> secondary capillary tract -> anterior pituitary
  • releases hormones into hypophyseal veins and on to systemic circulation via internal jugular vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what types of specialized neurons are present in the hypothalamus

A

glucose-sensing neurons
osmoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what type of cells produce growth hormone? where are they located?

A

somatotrophs
located in anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

under what conditions is growth hormone released?

A

in pulsatile bursts, major bursts at night
during slow wave sleep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the function of growth hormone binding protein?

A

transports GH
serves as a reservoir and prolongs half life to prevent degradation, otherwise free GH is broken down within 20 mins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

major functions of GH:

A

stimulates IGF-1 release from liver
stimulates postnatal longitudinal growth (anabolic and mitogenic effects)

17
Q

patterns of GH production/secretion across life

A

decreases after first 1-2 years of life
peaks in puberty
declines in adulthood and as we continue aging

18
Q

conditions that stimulate GH secretion

A

GHRH is triggered by: hypoglycemia, arginine, catecholamines, dopamine
Ghrelin (stomach, pancreas, kidney, liver, hypothalamus)

19
Q

factors and conditions that inhibit GH secretion

A
  • somatostatin/GHIH: hyperglycemia, increased non-esterified fatty acids
  • IGF-1: inhibits GHRH release and stim GHIH
20
Q

functions of somatostatin
where is it synthesized

A
  • synthesized by many parts of the brain and other organs (pancreas, stomach)
  • binds to G-alpha-i-somatostatin receptor and promotes tyrosine phosphatase activity (deactivates things)
  • binds to K+ channels which hyperpolarizes cells and stops release of GH
21
Q

what should you know about GH receptor

A
  • belongs to class 1 cytokine receptor family
  • located on: liver, bone, kidney, adipose tissue, muscle, brain, eye, heart, immune cells
  • 2 binding sites allow GH receptors to dimerize when GH binds and dimerization increases JAK activity which leads to phosphorylation of tyrosine residues -> release of activators of transcription proteins/expression of GH-regulated genes
22
Q

what is the other name for IGF-1?

A

somatomedin

23
Q

functions of IGF-1
what is it regulated by

A

regulated by GH, PTH and reproductive hormones in bone
function: stimulates bone formation and turn over, protein synthesis, glucose uptake into muscles, mitogenic

24
Q

how IGF-1 levels vary across lifespan

A

low levels at birth
increases during childhood/puberty
begins declining in 3rd decade

25
Q

what is the most common cause of acromegaly?

A

due to somatotrope adenoma, resutling in an over secretion of GH

26
Q

in acromegaly, what are the effects on peripheral tissues?

A

bone: acral bone overgrowth, increased hand/foot size, mandibular enlargement with prognathism, wide space between incisor teeth

soft tissue: increased heel pad thickness, coarse facial features, large fleshy nose

27
Q

what is the impact of acromegaly on the CV system?

A
  • cardiomyopathy with arrhythmias (LV hypertrophy, decreased diastolic function, hypertension)
  • upper airway obstruction with sleep apnea (central sleep dysfunction, soft tissue laryngeal airway obstruction)
  • diabetes - hyperglycemia puts stress on insulin function
28
Q

under what conditions might gigantism occur?

A

if increased GH secretion occurs before epiphyseal long bone closure in children or adolescents

29
Q

what type of cells are responsible for secreting prolactin? where are these cells located?

A

lactotrophs in the anterior pituitary

30
Q

what is a condition where the amount of lactotrophs would increase?

A

pregnancy
in response to estrogen

31
Q

functions of prolactin

A

development of mammary glands and milk production
maintain milk synthesis
inhibit GnRH

32
Q

when are prolacin levels elevated and reduced?

A

increases during sleep and reduces during waking hours

33
Q

what stimulates release of prolactin

A

increased estrogen
sucking - results in dopamine release from hypothalamus, causing prolactin to be released
GnRH (regulates FSH and LH)
serotoninergic and opioidergic pathways
prolactin releasing factors: TRH, oxytocin, vasoactive intestinal peptide

34
Q

why is prolactin not constantly being released?

A

it is under tonic inhibition from the dopamine binding to D2 receptors on the lactotrophs
dopamine released from hypothalamus will all the time inhibit prolactin
stomatostatin and GABA also exert inhibitory effect, just to a lesser extent than dopamine

35
Q

when someone is lactating, why is there sometimes a delay in menstrual cycle?

A

because prolactin inhibits GnRH which would stimulate FSH and LH that normally regulate the menstrual cycle

36
Q

where are prolactin receptors located?

A

mammary gland
ovary
brain

37
Q
A

BMS200 (3 decks)

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