P1 Spring Organs Chapter 75

Front 1

What does ACTH/Corticotropin cause the adrenal cortex to do?

Back 1

Secrete ACH(adrenal cortical hormone), which raises the blood glucose level and indirectly promotes insulin secretion.

Front 2

Cell types for:

•hGH
•ACTH
•TSH
•LH
•PRL
•FSH

Back 2

•hGH (somatotropes)
•ACTH (corticotropes)
•TSH (thyrotropes)
•LH (gonadotropes*)
•PRL (lactotropes)
•FSH (gonadotropes*)
remember that GnRH causes anterior pituitary to secrete LH and FSH

Front 3

What does TSH do?

Back 3

Stimulates production of thyroid hormones T3 and T4 by thyroid follicular cells.

Front 4

What does FSH do?

Back 4

•Stimulates development of ovarian follicles.
•Regulates spermatogenesis in testes.

Front 5

What does LH do?

Back 5

•Causes ovulation
•Formation of corpus luteum in ovary
•Stimulates production of estrogen and progesterone by ovary
•Stimulates production of testosterone in testes

Front 6

What does GH do?

Back 6

•promotes growth
•stimulates secretion of IGF-1
•liposis: adipose -> FFA -> acetyl CoA (produced by liver, used for energy)
•blocks uptake of lipids (no storage)
•decreases glucose utilization for energy (glucose is used to make carbs for growth)
•increases gluconeogenesis by liver (more glucose)
•increases insulin secretion but blocks its action of glucose storage (insulin is needed for growth)
•increase protein synthesis (more proteins for growth)

Front 7

What does the hypothalamus control and how?

Back 7

regulates release of hormones by the:

•pituitary (via stimulatory/inhibitory hormones)
•adrenal medula (via stimulation of sympathetic nervous system)

Front 8

What hormone(s) are released in pulses?

Back 8

•GH
•prolactin

Front 9

List factors that stimulate GH secretion

Back 9

•low glucose, low FFA (free fatty acids), protein deficiency
•low caloric intake, fasting
•stress, exercise
•sleep
•puberty
•androgens, estrogens

Front 10

List factors that inhibit GH secretion

Back 10

•high glucose, high FFA
•GH itself (neg feedback)
•somatostatins (somatotrope inhibitors)
•somatomedins (somatotrope stimulators, neg feed?)
•cortisol (inc gluconeogenesis/glucose)
•high protein(treatment)
•senescence(old cells dont divide well)

Front 11

List hormones that positively and negatively regulate GH secretion

Back 11

positive regulators:

•GHRH
•dopamine
•5-HT
•ghrelin
•a2 adrenoceptor agonists

negative regulators:

•somatostatin
•IGF-1 and GH (via neg feedback)
•beta adrenoceptor agonists

Front 12

Whats the normal path (start to finish) of GH?

Back 12

1.hypothalamus produces GHRH
2.GHRH stimulates anterior pituitary to secrete GH
3.GH attaches to target cell receptors

Front 13

List the causes of dwarfism

Back 13

No growth in long bones due to one of these:

•hypothalamus not producing GHRH
•anterior pituitary not producing GH
•mutation in GH receptors on target cells

Front 14

What does adult GH deficiency cause(list)?

Back 14

•CV disease
•unhealthy fat distribution
•loss of muscle mass
•impaired psychosocial function
•pituitary adenomas (90%)

Front 15

Similarities and differences betwen gigantism and acromegaly?

Back 15

Similarities:

•excess GH (and IGF)
•caused by pituitary tumor
•treated with surgery, radiation

Differences:

•acromegaly occurs after long bone growth plates have fused preventing additional growth
•acromegaly has soft bone growth

Front 16

List stimulators of prolactin

Back 16

•suckling
•stress, exercise
•sleep
•hypoglycemia
•estrogen and progesterone
•TRH/thyrotropin releasing hormone (stimulates TSH release from anterior pituitary)
•TSH/thyrotropin
•VIP/vasoactive intestinal polypeptide

Front 17

Negative regulator(s) of prolactin secretion?

Back 17

dopamine (prolactin inhibitor)

Front 18

What does hyperprolactinemia cause(list)?

Back 18

•amenorrhea(eg no menstrual for > 3 months)
•infertility (men and women)
•galactorrhea (inappropriate lactation)
•impotence(men)
•loss of libido

Front 19

List causes of hyperprolactinemia

Back 19

•Pituitary tumors
•Diseases that decrease dopamine (dopamine is an inhibitor of prolactin)
•HYPOthyroidism (causes high TSH, a stimulator of prolactin). Ironically, low TSH can cause hypothyroidism.

Front 20

Treatment of hyperprolactinemia?

Back 20

Dopamine agonists

Front 21

List hormones produced in the hypothalamus and stored in the posterior pituitary.

Back 21

•ADH/vasopressin
•oxytocin

Front 22

List functions of oxytocin.

Back 22

•contraction of uterine smooth muscle
•contraction of mammary myoepithelium around alveolar ducts (puts milk into ducts)
•men: contraction of prostate smooth muscle during ejaculation
•pregancy: impedes blood flow, dilates cervix, increases strength and rate of contractions
•promotes trust between mates, or mom and baby

Front 23

Inhibitor(s) of oxytocin?

Back 23

progesterone

Front 24

Whats the "let-down reflex"?

Back 24

contraction of myoepithelial cells around alveolar ducts that puts milk into ducts (all due to oxytocin)

Front 25

Function(s) of ADH?

Back 25

•increases sodium and water retention/reabsorption (by kidneys)
•released when blood volume is low
•smooth muscle contraction (at high concentrations)

Front 26

Site of action of ADH?

Back 26

collecting tubules and ducts

Front 27

What can diabetes insipidus cause, and how?

Back 27

Excessive urine production

Defect in area of hypothalamus that produces (or senses) ADH

Front 28

What is produced in the pancreas, and inhibits GH and insulin release?

Back 28

somatostatin

Front 29

What inhibits secretion of prolactin, and stimulates production of GHRH (increasing GH indirectly)?

Back 29

dopamine