Brainscape's Knowledge GenomeTM

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


See full index

(SALMA) Physiology > Endocrinology (pit/panc/thy) (SUGER) > Flashcards

Endocrinology (pit/panc/thy) (SUGER) Flashcards

1
Q

what is the main purpose of the endocrine system

A

to release hormones directly into the blood

allows rapid adaptive changes

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

what is the pituitary gland aka

A

hypophysis

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

where is the pituitary gland located

A

depression in the SPHENOID bone at the base of the brain, just below the hypothalamus (sella turcica)

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

how is the pituitary gland connected to the hypothalamus

A

by the infundibulum (pituitary stalk), containing axons from hypothalamus neurones and small blood vessels

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

what is the pituitary gland composed of

A

2 adjacent lobes: anterior and posterior

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

what is sig about the embryology of the pituitary gland’s lobes

A

both develop from diff tissues before joining together

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

which hormone(s) has a positive feedback loop (pituitary gland)

A

oxytocin

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

which hormone(s) has a negative feedback loop (pituitary gland)

A

all but oxytocin

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

what is the role of the hypothalamus

A

homeostasis (thirst, sleep, temp)

- controls endocrine function via pituitary

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

what are the 5 hormones released by the hypothalamus

A
  • CRH (corticotropin-releasing hormone)
  • GHRH (growth hormone-releasing hormone)
  • SST (somatostatin)
  • TRH (thyrotrophin-releasing hormone)
  • GnRH (gonadrotropin-releasing hormone)
  • DA (dopamine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does CRH do

A

stimulates release of ACTH (adrenocorticotropic hormone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what des GHRH do

A

stimulates GH release

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

what does SST do

A

inhibits release of GHRH

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

what does TRH do

A

stimulates release of TSH (thyroid-stimulating hormone)

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

what does GnRH do

A

stimulates release of LH/FSH

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

what does DA do

A

inhibits prolactin release (negative control by dopamine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

are there neural connections btwn hypothalamus and ant pit?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

does the anterior pituitary gland have a blood supply

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how does the ant pit gland receive blood?

A
  • through a portal venous circulation from hypothalamus (superior hyphoseal)
  • offers a local route for blood to be delivered directly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

does the posterior pituitary gland have a blood supply

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is a hypophysiotropic hormone

A

collective term for a hypothalamic hormone that regulates ant pituitary gland function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

how many hormones does the anterior pituitary gland secrete

A

6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

list the 6 peptide hormones the ant pit secretes

A
  1. FSH
  2. LH
  3. ACTH
  4. TSH
  5. Prolactin
  6. GH

(FLATP(I)G)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where is FSH prod

A

gonadotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what does FSH do

A

stimulates ovarian follicle growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is the mnemonic for hormones of the anterior pituitary

A

FLATPIG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

where is LH prod

A

gonadrotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what does LH do

A

stimulates ovulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

where is ACTH prod

A

corticotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what does ACTH do

A

stimulates adrenal cortex to secrete cortisol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

where is TSH prod

A

thyrotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what does TSH do

A

stimulates thyroid to release thyroxine (T3/T4) thus increasing metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

where is prolactin prod

A

lactotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what does prolactin do

A

stimulates lactation, helps breast development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

where is GH prod

A

somatotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what does GH do

A

stimulates growth and protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

give an overview of what TRH does

A

TRH –> TSH –> incr release of T3/4 from thyroid –> increased metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

give an overview of what GnRH does

A

GnRH –> LH/FSH –> targets gonads to increase oestrogen, progesterone & testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

give an overview of what GHRH does

A

GHRH –> GH –> stimulates growth and protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

give an overview of what SST does

A

SST –> inhibits GH –> inhibits growth and protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

give an overview of what CRH does

A

CRH –> ACTH –> increases cortisol prod in adrenal cortex

42
Q

give an overview of what DA does

A

DA –> inhibits prolactin –> inhibits growth and milk prod

43
Q

why is long-loop neg feedback important in eg cortisol

A
  • stressful stimulation = increased CRH thus increased ACTH and then cortisol
  • elevation of plasma cortisol –> inhibits CRH-secreting neurones and also ACTH-secreting cells of ant pit
  • so, cortisol doesn’t increase that much –> important bc of damaging effects of excess cortisol on immune function & metabolic reactions
44
Q

name an example of short-loop negative feedback

A

prolactin: acts on hypothalamus to stimulate DA secretion which then inhibits prolactin secretion

45
Q

what are the 2 main ways in which ant pit tumours can present

A

pressure on local structures (optic nerves, bitemporal hemianopia)

pressure on normal pituitary (excess/inadequate release of pituitary hormones)

46
Q

does the post pit prod hormones

A

no

47
Q

what does the post pit do

A

stores and releases 2 peptide hormones that are prod by hypothalamus (ADH and oxytocin)

48
Q

where is ADH synthesised

A

hypothalamus: in the cell body of the SUPRAOPTIC NUCLEUS

49
Q

where is oxytocin synthesised

A

hypothalamus: in the cell body of the PARAVENTRICULAR NUCLEUS

50
Q

where do the axons of the supraoptic/paraventricular nuclei pass

A

down the pituitary stalk and terminate in the post pti

51
Q

what does ADH do

A
  • increases renal fluid reabsorption (aquaporins)

- acts on blood vessels to cause vasoconstriction thus incr BP

52
Q

what does oxytocin do

A

provides positive feedback system during labour (stimulates lactation)

53
Q

what is ADH released in response to

A
  • decreased blood vol
  • trauma, stress
  • increased blood carbon dioxide
  • decreased blood oxygen
  • increased osmotic pressure of blood
54
Q

which receptors do all pituitary/hypothalamic hormones act on

A

G-protein coupled receptors

55
Q

where does the pancreas lie

A

retroperitoneal, lies post to greater curvature of stomach (head lies near c-portion of duodenum)

56
Q

what are acini

A

small clusters of glandular epithelial cells

57
Q

what is the exocrine function of the pancreas performed by

A

acinar cells

58
Q

what % of pancreatic cells are acini & islet of langerhan cells

A 
98-99% = acini
1-2% = islet of langerhans cells
59
Q

what are the 3 cells of the islets of langerhans

A

alpha
beta
delta

60
Q

what do alpha cells secrete

A

glucagon

61
Q

what do beta cells secrete

A

insulin

62
Q

what do delta cells secrete

A

somatostatin

63
Q

what kind of actions do insulin and glucagon have

A

reciprocal

64
Q

what is glycogenolysis

A

breakdown of glycogen to glucose

65
Q

what is gluconeogenesis

A

formation of glucose from non-carb substrates

66
Q

what does insulin do

A
  • suppresses hepatic glucose output (decreased glycogenolysis/gluconeogenesis)
  • increases glucose uptake into insulin sensitive tissues
  • suppresses lipolysis
  • suppresses muscle breakdown (decreased ketogenesis)
67
Q

what does glucagon do

A
  • increases hepatic glucose output (increases glycogenolysis/gluconeogenesis)
  • reduces peripheral glucose uptake
  • stimulates peripheral release of gluconeogenic precursors ie glycerol and amino acids
  • stimulates lipolysis
  • stimulates muscle glycogenolysis and breakdown (increased ketogenesis)
68
Q

what is the precursor of insulin

A

proinsulin

69
Q

what are the 4 steps in insulin secretion

A
  1. glucose enters beta cells via GLUT2 transporter
  2. glucokinase metabolises glucose –> glycolysis & Krebs prod ATP
  3. ATP closes K+ channel –> no K+ efflux –> cell depolarises (ie becomes more positive)
  4. depolarisation –> Ca2+ influx (voltage gated channels that open when depolarisation occurs) –> exocytosis of insulin
70
Q

describe the 3 steps in insulin action

A
  1. insulin binds to insulin receptor on target cell
  2. increased exocytosis of GLUT4 vesicles to cell membrane –> more GLUT4 vesicles in cell membrane
  3. increased glucose uptake through GLUT4 receptors (thus decreasing blood glucose levels)
71
Q

what is the liver’s ST response to high blood glucose

A

glycogenesis (glucose –> glycogen)

72
Q

what is the liver’s LT response to high blood glucose

A

lipogenesis (formation of triglycerides)

73
Q

what is the liver’s ST response to low blood glucose

A

glycogenolysis (glycogen – glucose)

74
Q

what is the liver’s LT response to low blood glucose

A

gluconeogenesis (amino acids/lactate –> glucose)

75
Q

where are there glucose sensors

A

primary in islets of langerhans, then also medulla, hypothalamus and carotid bodies

76
Q

what happens in the fasting state?

A

ALL glucose comes from liver

  • gluconeogenesis (pyruvate from glucose-alanine cycle)
  • hepatic glycogen stores utilised - glucagon

low insulin levels - glucose supplied to brain/rbc (insulin dependant tissues)

77
Q

what happens in the fed state?

A
  • rising glucose levels increases insulin synthesis and decreases glucagon synthesis
  • glucose travels to liver (40%) /muscle (60%) –> replenishes glycogen stores
  • excess glucose –> fat in adipocytes
78
Q

what is hypoglycaemia

A

low blood glucose

79
Q

what is high blood glucose

A

hyperglycaemia

80
Q

where is the thyroid gland located

A

C5-T1, inferior to thyroid cartilage
behind sternohyoid/sternothyroid muscles
wraps around cricoid cartilage/sup tracheal rings

81
Q

what is the structure of the thyroid

A

divided into 2 lobes, connected by an isthmus

82
Q

what is the blood supply of the thyroid gland

A

sup & inf thyroid arteries (paired)

83
Q

what is the superior thyroid artery a branch of

A

external carotid artery

84
Q

what is the inferior thyroid artery a branch of

A

subclavian artery

85
Q

what is the venous drainage of the thyroid gland

A

jugular vein

86
Q

what are the 2 cell types of the thyroid gland

A

follicular cells and c cells

87
Q

what do follicular cells produce

A

t3 and t4

88
Q

what do c cells secrete

A

calcitonin

89
Q

what is t3

A

triiodothyronine (biologically active)

90
Q

what is t4

A

thyroxine (de-iodinisedin peripheral tissues to form t3

91
Q

how are t3 and t4 carried in the bloodstream

A

bound to albumin and thyroxine binding protein

92
Q

what is the function of thyroid

A

absorption of iodine

93
Q

what is the function of thyroxine

A

conversion to t3

94
Q

what is the major thyroid hormone

A

t3

95
Q

does t3 have a higher blood conc or t4

A

t4

96
Q

what can t4 be thought of as

A

a reservoir for additional t3

97
Q

list the 4 steps in thyroid hormone synthesis

A
  1. TSH released from ant pit
  2. Na/I symporter increases iodine uptake
  3. thyroglobulin iodinised - catalyses by thyroperoxidae
  4. thyroglobulin + tyrosine –> thyroxine (T3/T4)
98
Q

what does t3 do

A
  • incr metabolic rate

- important in brain maturation

99
Q

what do the parathyroid glands do

A

regulate calcium and phosphate levels

100
Q

when does the parathyroid gland secrete PTH

A
  • low calcium levels

- high phosphate levels

101
Q

whats the difference btwn endogenous and exogenous insulin

A

endogenous insulin has C peptide attached - exogenous is free insulin

(SALMA) Physiology (12 decks)

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