Endocrine

Question 1

describe the difference between the exocrine and endocrine systems

Answer 1

exocrine - ducts

endocrine - ductless

Question 2

Hormones are chemical messengers that regulate body processes like (5)

Answer 2

o	Growth and development – physical and mental 
o	Metabolism
o	Sexual function
o	Reproduction
o	Mood stability

Question 3

pineal gland is responsible for

Answer 3

receive and modulate information about the day vs. night cycle
o secretes melatonin

Question 4

what does Growth hormone (GH) stimulate

Answer 4

stimulates growth of bone and muscles, determined by genes but maximized by the growth hormones

Question 5

what does prolactin (PRL) do

Answer 5

part of the anterior pituitary gland, prepares females for breast feeding, level is elevated during pregnancy and breast feeding

Question 6

what does adrenocorticotropic hormone (ACTH) do

Answer 6

stimulates the synthesis and secretion of adrenocortical hormone

Question 7

what does thyroid-stimulating hormone (TSH) do

Answer 7

stimulate the synthesis of thyroid hormone

Question 8

what does follicle-stimulating hormone (FSH) do

Answer 8

affects both males/females. In the females it stimulates the growth of ovarian follicles and ovulation. In males, it stimulates sperm production = spermatogenosis

Question 9

what does luteinizing hormone (LH) do

Answer 9

for females, it stimulates the development of corpus luteum, the release of oocytes, and production of estrogen and progesterone but mainly progesterone. In males, stimulates the production of testosterone.

Question 10

anterior pituitary gland secretes what hormones? (6)

Answer 10

1. Growth hormone (GH)
2. prolactin (PRL)
3. adrenocorticotropic hormone (ACTH)
4. thyroid-stimulating hormone (TSH)
5. follicle-stimulating hormone (FSH)
6. luteinizing hormone (LH).

Question 11

posterior pituitary gland secretes what hormones? (2)

Answer 11

1. oxytocin

2. antidiuretic hormone (ADH) or vasopressin

Question 12

what does oxytocin do?

Answer 12

stimulates the contraction of the pregnant uterus, and milk ejection for breast feeding after childbirth; as opposed to prolactin, it is responsive to the action of breast feeding only

Question 13

what does ADH/vasopressin do?

Answer 13

increase water reabsorption

Question 14

what does the hypothalamus do?

Answer 14

regulates the pituitary gland particularly the anterior pituitary gland; the posterior pituitary gland is controlled by brain.
o The master of the master (pituitary gland)

Question 15

what does the pancreas do?

Answer 15

o Has both exocrine and endocrine function – we focus on endocrine fxn
o Endocrine function- carried out by islets of Langerhans – about 1 million islets of Langerhans

Question 16

name and describe the 2 main Langerhans cells

Answer 16

o Alpha cells- secrete glucagon, increases BG level

o Beta cells- secrete insulin, decreases BG level

Question 17

where is the thyroid gland located

Answer 17

Located at the base of the neck below the larynx

- contains several functional units called follicles

Question 18

what 3 hormones are produced from the thyroid gland follicles

Answer 18

• thyroxine (T4)
• triiodothyronine (T3)
• thyrocalcitonin or calcitonin – lowers the blood calcium level

Question 19

when TSH stimulates the thyroid gland to secrete T3 and T4, what happens in the body?

Answer 19

• increase the metabolic rate, necessary for fetal growth and development
• increases the body’s responsiveness to catecholamines

Question 20

where is the parathyroid gland located?

Answer 20

Usually 4 in number; located in the posterior surface of the thyroid gland

Question 21

what does the parathyroid gland do?

Answer 21

Secretes parathyroid hormone (PTH)- increases serum calcium level

Question 22

what is within the adrenal glands?

Answer 22

Located in each kidney; each gland has inner (medulla) and outer portion (cortex)

Question 23

what does the medulla produce and when?

Answer 23

produces epinephrine and norepinephrine during times of stress

Question 24

describe the outermost region of the cortex

Answer 24

produces mineralocorticoids-

• Principal mineralocorticoid: Aldosterone

Question 25

describe the middle region of the cortex

Answer 25

produces glucocorticoids- • Principal glucocorticoid: cortisol – affects metabolism, regulates BG level, affects growth, anti-inflammatory functions, decreases the effect of stress • If the cortisol level is very low, even a mild stress could be life-threatening

Question 26

describe the innermost region of the cortex

Answer 26

produces gonadocorticoids (sex hormone) • Male hormone- Androgen • Female hormone- Estrogen • Note: secreted only in minimal amount; hormones from the testes and ovaries mask their effects

Question 27

when does SIADH occur

Answer 27

happens when there is excessive secretion of ADH from the posterior pituitary gland or other areas outside the mentioned gland

Question 28

what are the causes of SIADH

Answer 28

most common: carcinoma; these include carcinoma of the tongue, lung, duodenum, pancreas, connective tissues, as swell as leukemia, lymphoma, and Hodgkin’s disease. o Post-surgery monitor their urinary output for SIADH

Question 29

when can transient SIADH be seen?

Answer 29

pituitary surgery, use of certain drugs (barbiturates, general anesthetics, vincristine, nicotine, morphine)

Question 30

what is the normal process for increased extracellular fluid volume (decreased urine output) to balance when the body is dehydrated?

Answer 30

1. Elevated serum concentration and/or decrease in extracellular fluid volume/dehydration 2. stimulates post pituitary gland to secrete ADH 3. ADH increases kidney’s permeability to water = increased water reabsorption (to the plasma) 4. decreased urine formation (end result goal: increased extracellular fluid volume).

Question 31

In SIADH, ADH is secreted unrelated to the main stimuli (even if you’re not dehydrated)?

Answer 31

1. Increased ADH = increased water reabsorption in the kidney 2. extracellular fluid increases in the blood vessels 3. dilution of serum Na (low serum Na = hyponatremia); highly concentrated urine S/S- related to low Na level- fatigue, weakness, confusion.

Question 32

what are normal Na levels vs SIADH Na levels

Answer 32

Normal 135-145 mEg/L !!! Na serum level below 115 mEq/L produces confusion, lethargy, muscle twitching, seizure, coma, and possibly irreversible neurologic damage Take Home point: key feature of SIADH: water retention, low serum sodium and concentrated urine!

Question 33

management for SIADH

Answer 33

Treat the underlying cause (hyponatremia in SIADH) = so increasing urine volume and the serum Na level o Demeclocycline (Declomycin) o Hypertonic IV o Diuretic

Question 34

what is diabetes insipidus (DI)

Answer 34

result in a deficiency of ADH | - 2 types: neurogenic DI; and Nephrogenic DI

Question 35

describe neurogenic DI

Answer 35

ADH is missing or low secondary to malfunction of the post pituitary gland. o For example, brain tumor and radiation atrophies the pit gland = neurogenic DI

Question 36

describe nephrogenic DI

Answer 36

ADH is produced normally but distal tubules and collecting ducts (nephrons) cannot respond to hormone’s signal to reabsorb water. o Kidneys are insensitive!

Question 37

why is ADH released into the bloodstream

Answer 37

ADH is released into the bloodstream when needed to cause kidney to reabsorb water.

Question 38

In DI, water cannot be reabsorbed which leads to what?

Answer 38

In DI, water cannot be reabsorbed - > passed out as urine - > large volume of urine

Question 39

clinical manifestations of DI

Answer 39

o Change in mentation; insomnia; o Polydipsia (increased thirst); weight loss from the loss of fluids o Nocturia (peeing at night); urinary frequency; o Increased urine output- as much as 4 to 18 liters per day!

Question 40

treatment of DI

Answer 40

``` o Treat the underlying cause o Desmopressin (DDAVP)- IV, subcutaneous, intranasal • ONLY for neurogenic DI o Pitressin- intramuscular • Synthetic antidireutic hormone ``` o Nephrogenic: thiazide diuretic, prostaglandin inhibitors (NSAIDs) • If the person is already peeing gallons, why give diuretics, the etiology must be nephrogenic, the pee will lessen