Brainscape's Knowledge GenomeTM

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


See full index

Chemical Pathology > Hypothalamo Pituitary Gonadal Axis > Flashcards

Hypothalamo Pituitary Gonadal Axis Flashcards

1
Q

The GnRH secreting neurons are located in a discrete nucleus in the hypothalamus. T/f

A

F…they are diffusers distributed in the hypothalamus

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

The GnRh has how many amino acids?

A

10 making it a decapeptide

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

The GnRh is stimulated by neurons that secrete?

A

KING
Kisspeptin which stimulates the release of GnRH, inhibited by estradiol
Norepinephrine
Neuropeptide Y
Glutamate
Galanin like peptide

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

The pulsatile release of GnRH is essential to gonadotroph responsiveness because?

A

Tonic or sustained release of GnRH would downregulate GnRH receptors on gonadotrophs leading to hypogonadism

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

Regulation of GnRH

A

Draw the diagram

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

4 things to remember about Fsh

A

Glycoprotein
Also called follitropin
Has a non specific alpha and specific beta subunits
Receptor is present on granulosa cells

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

Function of fsh

A

When stimulated by fsh,granulosa cells use theca cells androstenedione as the precursor for estradiol synthesis
Also stimulates the expression of lH receptors on theca cells
Stimulate the growth and maturation of ovarian follicles
Promotes via estrogen, the endometrial changes of the first portion of the menstrual cycle ..I e proliferative or follicular phase

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

Functions of LH

A

Promote and maintain the second phase of the menstrual cycle(secretory or luteal phase)

Assist in the formation and maintenance of the corpus luteum

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

Lh receptors are expressed on what cells in females

A

Theca cells

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

In females, estrogen and inhibin regulaye Lh and fsh secretion respectively. T/f

A

T

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

The principal estrogen produced in the ovary

A

Estradiol(E2)

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

E2 is produced primarily by

A

Ovarian follicles
Corpus luteum
And in pregnancy by the placenta

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

Oestrogen affect calcium homeostasis as they…..

A

Decrease bone resorption

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

Major sources of progesterone in non pregnant and pregnant women

A

Corpus luteum and placenta respectively

Minor sources include the adreal cortex in both sexes and testes in men

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

Progesterone is a glycoprotein hormone. T/f

A

F…a carbon 21 compound within the steroid family

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

Functions of progesterone

A

Thickening of cervical mucus
Reduces uterine contraction
Thermogenesis effect..which is of clinical use in marking occurrence of ovulation

17
Q

The dominant hormone of luteal phase

A

Progesterone.
Luteal failure*

18
Q

Lactational Amenorrhea occurs due to

A

Hyperprolactinemia which causes hypogonadism either by inhibiting gonadotropin secretion from the pituitary or by inhibition of gonadotropin action at the gonad

19
Q

Increased stress or emotional stress can lead to Irregular menstruation. T/f

A

T

20
Q

Normal prolactin levels

A

6-19.5ng/ml
In pituitary gland tumor…levels may be severely increased. To hundreds

21
Q

The ovaries produce small amounts of a carbon 19 compound known as

A

Testosterone

22
Q

Functions of inhibin A and B

A

Inhibit FSH production

23
Q

Typical duration of menstrual bleeding? With an average blood loss of?

A

3-5 days
50mls

24
Q

Hormonal control of ovulation

A

T

25
Q

Group 1 ovulation disorder

A

Caused by hypothalamic pituitary failure
Eg hypothalamic Amenorrhea, hypogonadotrophic hypogonadism

26
Q

Group 2 ovulation disorder

A

Due to dysfunctions of the hypothalamic pituitary ovarian axis.
Eg PCOS, hyperprolactinemic Amenorrhea

27
Q

Group 3 ovulation disorder

A

Due to ovarian failure

28
Q

Normally FSh levels should be less than 15 and lh levels less than 9 around the early phase of the menstrual cycle days 3 -5

A

T…thus higher levels indicate that ovaries are already failing and may not be able to release ovum
Also indicates poor ovarian reserve Prospective assessment of fertility and ovulation

29
Q

Progesterone should be greater than 10dl/…normal for fertile individuals

A

True

30
Q

GnRh is secreted and released via what tract

A

Portal hypophysial tract

31
Q

In males ,Fsh acts on

A

Sertoli cells and spermatocytes

32
Q

In males,LH acts on

A

Leydig cells to stimulate conversion of cholesterol to pregnenolone which is the rate limiting step in testosterone biosynthesis.

33
Q

What hormone is extremely important in investigating for msle infertility

A

Testosterone

34
Q

Testostosterone is synthesised primarily by?

A

Leydug cells of the testes(95%)
And to a lesser extent from the androgens synthesised in the ZR of the adrenals

35
Q

Testosterone levels are highest at midnight. T/f

A

False ,highest in the morning

36
Q

Hyperprolactinemia effects in males

A

Infertility

37
Q

Retrospective assessment

A

When assessment of ovulation is done days after ovulation like 20-25 days

Chemical Pathology (1 decks)

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