Brainscape's Knowledge GenomeTM

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


See full index

Physiology Endocrine > Pituitary Hormones > Flashcards

Pituitary Hormones Flashcards

1
Q

body functions dictated by the posterior pituitary gland

A

water balance

blood volume

intake - thirst

output - urine volume

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

body functions dictated by the anterior pituitary gland

A

metabolic rate

stress response

growth

reproduction

lactation

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

2 types of neurosecretory cells in hypothalamus

A

magnocellular

parvocellular

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

median eminence

A

neurovascular region of hypothalamus

where neurohormones are transported to once made in the neuronal bodies

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

corticotroph

A

15-20% of anterior pit

products:

  1. ACTH –> adrenal gland
  2. beta-lipotropin –> adipose and melanocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

thyrotroph

A

3-5% of anterior

TSH –> thyroid gland

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

gonadotroph

A

10-15% of anterior

LH –> gonads

FSH –> gonads

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

somatotroph

A

40-50% of anterior

GH –> all tissues

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

mammotroph

A

10-25% of anterior

prolactin –> breasts, gonads

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

how are anterior pituitary hormones secreted

A

pulsatile fashion

for efficient and effective signaling of target tissues for the ability to change the signal strength and regulating ongoing metabolic clearance of the hormone

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

regulation mechanisms of anterior pituitary hormones

A
  1. releasing and inhibiting hormones from hypothalamus

2. negative feedback mechanism

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

corticotropin

A

39 amino acids

precursor molecule = POMC

first 18 amino acids have full biological activity…first 24 are identical across species

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

modification of POMC

A

cleaved into beta-lipotropin, ACTH, and NH2-terminal peptide

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

modification of corticotropin during fetal life and at end of pregnancy

A

cleaved into melanocyte stimulating hormone and cotricotropin like peptide (cotricotropin)

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

modification of beta-lipotropin during fetal life and at end of pregnancy

A

split into lipotropin and beta-endorphin

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

effect of stress and sleep-wake on ACTH secretion

A
    • hypothalamus to secrete corticotropin releasing hormone (CRH)
    • anterior pit to release ACTH
      - which negatively regulates CRH secretion from hypothalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

ACTH effect on adrenal gland

A

(+) cortisol release from adrenal gland

cortisol negatively regulates

  1. CRH release from hypothalamus
  2. ACTH release from anterior pituitary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

2 molecules released from hypothalamus that (+) ACTH release from anterior pituitary

A

CRH and ADH

19
Q

molecule released from hypothalamus that (-) ACTH release from anterior pituitary

A

BNP

20
Q

NE, ACh, and serotonin on hypothalamus

A

(+) release of ANP and CRH –> (+) ACTH

21
Q

gamma-aminobutyric acid

endorphins

ACTH itself

cortisol

EFFECTS on hypothalamus

A

(-) release of ANP and CRH –> (-) ACTH

22
Q

prolactin-GH hormone family

A

GH, hPL, hCS

share amino acid sequence homologies

can be divided into GH and prolactin sub-families

23
Q

glycoprotein hormone family

A

FSH, LH, and Thyrotropin

each consists of 2 noncovalently linked subunits alpha and beta

  • alpha is common to all 3
  • beta is unique to each and confers specificity

alpha subunit is considered to be more abundant than the unique beta

24
Q

FSH and LH levels after menopause

A

increase

25
Q

general regulation of FSH and LH

A

integration of LHRH (GnRH) signal

feedback effects of gonadal steroids

peptide hormones (inhibin)

26
Q

effects on gonadal steroids and peptide hormones on FSH and LH release without LHRH

A

ineffective…need LHRH to for those to have any effect at all

27
Q

rate of LHRH pulse per hour for maintaining LH and FSH secretion

A

1 pulse per hour

28
Q

when LHRH pulse frequency is decrease to 1 every 3 hours…

A

FSH secretion is preferentially stimulated

29
Q

more frequent LHRH pulses…

A

initially increase frequency of LH pulse and mean LH concentrations

30
Q

estradiol (ovaries) and dihydrotestosterone (testes)

A

negative feedback on LHRH (GnRH) release and thus reduce release of LH

also inhibits FSH and LH release directly by (-) pituitary release

31
Q

endorphin and Dopamine effect on hypothalamus in gonadotropin regulation

A

inhibits hypothalamic release of GnRH

32
Q

NE effect on hypothalamus in gonadotropin regulation

A

stimualtes hypothalamic release of GnRH

33
Q

Follistatin, Inhibin, and Activin

A

released from gonads (peptide hormones) upon FSH and LH stimulation

follistatin –> (-) pituitary FSH

inhibin –> (-) pituitary FSH and hypothalamus GnRH

activin –> (+) pituitary for FSH

34
Q

neurohormones secreted by posterior pituitary

A

ADH (AVP)

oxytocin

very close in structure (only 2 of the 9 amino acids are different..and same disulfide bond is present)

35
Q

amino acid difference between ADH and oxytocin

A

ADH: X-X-Phe-X-X-X-X-Arg-X

Oxytocin: X-X-lle-X-X-X-X-Leu-X

closeness causes overlap in hormone effects

36
Q

neurophysins

A

I = for OTC

II = for ADH

packaged and secreted with these…without them, the hormones remain in the secretary vesicles

37
Q

four factors that regulate ADH secretion

A

osmolarity

body fluid volume

CSF concentration of Na+

changes in body temperature

38
Q

osmoreceptors for ADH secretion

A

located in anterior hypothalamus…mainly on neurons of the OVLT

as little as 1% rise in osmolarity will increase their firing and stimulate ADH producing neurons in the supraoptic nucleus and the paraventricular nucleus of the hypothalamus

thereby increase plasma ADH

39
Q

hypovolemia and ADH

A

increase ADH release with blood volume decreases by ~10%

located in the right atrium

40
Q

increase of Na+ in CSF

A

increases ADH via Na-sensors

41
Q

ADH through V1 and V2 receptors

A

ADH acts on V1a receptors –> causes vasoconstriction

V2 receptors (kidney) tend to counterbalance this effect

do this to conserve water and regulate plasma tonicity

42
Q

ADH effect on ACTH secretion

A

increases ACTH secretion –> (+) cortisol levels

43
Q

ADH activation of V2 receptors in kidney tubule and cortical collecting duct cells

causes antidiuresis in 3 ways

A
  1. stimulate Na/K-2Cl co transport in the thick ascending limb
  2. increase the permeability of the collecting duct to urea
  3. increase permeability of the collecting ducts to water
44
Q

body temperature on ADH secretion

A

increase = (+) ADH

Physiology Endocrine (7 decks)

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