Pituitary Gland Flashcards Preview

Physiology and Neuroscience > Pituitary Gland > Flashcards

Flashcards in Pituitary Gland Deck (35):
1

What is the pituitary gland?

"Master" endocrine glands because it secretes several hormones that control other endocrine glands

2

Where is the pituitary gland?

Small region of the brain below the thalamus
Lies in the hypophyseal fossa of the sella turcica of the sphenoid bone

3

What does the pituitary gland link?

The nervous and endocrine system

4

How many cells does the hypothalamus synthesise?

At least 9 different hormones

5

How many cells does the pituitary gland synthesise?

Seven

6

What is the shape and size of the pituitary?

Pea shaped structure
1-1.5cm

7

What does the pituitary gland attach to?

The hypothalamus by a stalk (infundibulum)

8

What are the two portions of the pituitary gland?

Anterior pituitary gland
Posterior pituitary gland

9

What are the two parts of the anterior pituitary gland in an adult?

Pars distalis (larger portion)
Pars tuberalis (forms sheath around infundibulum)

10

What is the posterior pituitary composed of?

Neural tissue

11

What does the posterior pituitary consist of?

Pars nervosa
Infundibulum

12

What's the third part of the pituitary gland?

Pars Intermedia (only in fetal development)

13

What are the six major anterior pituitary hormones?

GH (Somatotropin)
TSH (Thyroid stimulating hormone)
ACTH (Adrenocorticotropic hormone)
FSH (Follicle stimulating hormone)
LH (Luteinising hormone)
Prolactin

14

What is GH (Somatotropin) involved in?

Insulin-like growth factor (IGF-1) & metabolic effects

15

What is TSH (Thyroid stimulating hormone) involved in?

Secretion of thyroid hormones

16

What is ACTH (Adrenocorticotropic hormone) involved in?

Cortisol from adrenal cortex

17

What is FSH (Follicle stimulating hormone) involved in?

Inhibin from Sertoli cells, Corpus luteum
Oestrogen from granulosa cells of follicle

18

What is LH (Luteinising hormone) involved in?

Testosterone from Leydig cells
Progesterone from Corpus luteum

19

What is prolactin involved in?

Breast development & milk production

20

What are the six hypothalamic releasing factors?

GnRH (Gonadotropin Releasing Hormone)
GHRH (Growth hormone releasing hormone)
SST (Somatostatin)
TRH (Thryotropin, TSH-releasing hormone)
CRH (corticotropin releasing hormone)
Dopamine (amine not a peptide hormone)

21

What is GnRH (Gonadotropin Releasing Hormone) for?

Stimulates release of LH and FSH (production of gametes)

22

What is GHRH (Growth hormone releasing hormone) for?

Stimulates release of growth hormone, GH

23

What is SST (Somatostatin) for?

Inhibits release of growth hormone, GH

24

What is TRH (Thryotropin, TSH-releasing hormone) for?

Increase release of thyroid stimulating hormone, TSH

25

What is CRH (corticotropin releasing hormone) for?

Increases release of corticotropin (ACTH) may stimulate prolactin release

26

What is Dopamine (amine not a peptide hormone) for?

Decreases prolactin release

27

What is the anterior pituitary hormone feedback long and short control loops?

Stress and Non-stress neural inputs
Hypothalamus
Corticotropin releasing hormone (CRH)
Anterior Pituitary
Adrenocorticotropic hormone (ACTH)
Adrenal cortex
Cortisol (end product feedbacks)

28

What can the two additional hypothalamic hormones of the posterior pituitary hormones?

ADH (Anti-Diuretic Hormone)
Oxytocin

29

What is ADH released as a posterior pituitary hormone?

Also known as Vasopressin (two functions)
Causes production of hypertonic urine (dilute)
Causes increase in systemic mean arterial blood pressure

30

What is Oxytocin released as a posterior pituitary hormone?

Released as part of the suckling reflex
Causes contraction of smooth muscle cells (myo-epithelial cells and smooth muscle in breast duct cells to enhance milk flow- let down reflex)

31

What is Oxytocin also involved with?

Other sex hormones
Oestrogen- causes breast duct development in puberty
Progesterone and prolactin cause breast alveoli development
Prolactin stimulates breast milk production by alveolar cells

32

What are the two phases of the LH and FSH in female reproductive system?

Follicular phase
Luteal phase

33

What is the follicular phase for LH and FSH in female reproduction?

LH FSH
Thecal cells -> Androgens -> Granulosa cells
Inhibin Oestrogen
Inhibits FSH only Inhibits ant pit FSH & LH

34

What is the luteal phase in female reproduction?

Granulosa cells develop LH receptors and combine with thecal cells to produce progesterone which continues to inhibit LH production

35

What is the LH and FSH in the male reproductive system?

FSH -> Sertoli cells -> Sperm production

LH -> Leydig cells -> Testosterone