Physiology Endocrine System

Front 1

What does the endocrine system do?

Back 1

secretes products (hormones) directly into the blood

Front 2

Do endocrine glands have ducts?

Back 2

No (ductless compared to exocrine glands which utilized a specific duct system)

Front 3

What are four examples of hormones?

Back 3

-proteins/glycoproteins
-amine hormones
-steroids
-long fatty acid chains

Front 4

What are 5 actions of hormones?

Back 4

-plasma membrane permeability (i.e. ADH acting on the CD of the kidneys)
-gene activation
-organelle
-via secondary messenger system or direct
-amplification and specificity

Front 5

What is another name for the pituitary gland?

Back 5

hypophysis

Front 6

What is another name for the anterior pituitary?

Back 6

adenohypophysis

Front 7

What is another name for the posterior pituitary?

Back 7

neurohypophysis

Front 8

What are the outer and inner portions of the adrenal gland called?

Back 8

cortex-outer portion
medulla-inner portion

Front 9

What does the medulla of the adrenal gland secrete?

Back 9

Epinephrine/norepinephrine

Front 10

What does the gut secrete?

Back 10

gastrin, secretin, CCK (etc.)

Front 11

What hormone do the immune cells secrete?

Back 11

cytokines

Front 12

What hormone does the heart secrete?

Back 12

ANP (atrial natriuretic peptide)

Front 13

What 2 hormones does the kidney secrete?

Back 13

-EPO
-vitamin D3

Front 14

How many hormones does the anterior pituitary produce?

Back 14

8 hormones

Front 15

What are 4 things GH does?

Back 15

-protein synthesis (synergistic to insulin)
-carb and fat metabolism (antagonistic to insulin)
-induces gluconeogenesis
-bone tissue development

Front 16

What is GH abused by athletes?

Back 16

-provides energy from carbs and fats and builds muscle

Front 17

What is gluconeogenesis (function of GH)?

Back 17

conversion of non-carbs to carbs (antagonistic to insulin)

Front 18

What does gluconeogenesis do?

Back 18

-keeps blood glucose levels high
-can cause diabetes type 1 (B cells are highly fatigue prone, they will give up under constant stimulation to produce insulin)

Front 19

What is another term for GH?

Back 19

somatotropin

Front 20

Once the epiphyseal line develops, what no longer happens to the bone?

Back 20

It no longer grows lengthwise

Front 21

What is IGF-1 and what is it produced by?

Back 21

insulin-like growth factor 1, produced by the liver

Front 22

When do GH levels decrease significantly?

Back 22

by age 40 (this is relatively young)

Front 23

What does gigantism result from?

Back 23

excessive GH secretion prior to epiphyseal plate formation, usually caused by pituitary adenoma

Front 24

What is acromegaly?

Back 24

excessive GH secretion AFTER the epiphyseal plate forms

Front 25

What are gigantism and acromegaly both risk factors for?

Back 25

type II diabetes

Front 26

What is Laron dwarfism?

Back 26

-normal GH
-mutation of GH receptor
-low levels of IGF-1

Front 27

What happens in the other kind of dwarfism?

Back 27

-low levels of GH
-highly treatable

Front 28

What are the 8 hormones secreted by the anterior pituitary gland?

Back 28

1) GH
2)TSH
3) Gonadotropins (LH and FSH)
4) Prolactin (Leuteotropic Hormone or LTH)
5) Adrenocorticotropic Hormone (ACTH)
6) B-Lipotropin (B-LPH)
7) Melanophore Stimulating Hormone (MSH)
8) B-endorphin (BE)

Front 29

What is prolactin (leuteotropic hormone or LTH)?

Back 29

-milk production
-immune system modulator

Front 30

What is adrenocorticotropic hormone (ACTH)?

Back 30

-goes to adrenal cortex
-important for mediating stress

Front 31

What is B-lipotropin (B-LPH)?

Back 31

fat metabolism (not entirely sure though...)

Front 32

What is MSH?

Back 32

-immune function
-melanocytes
-regulator of food intake (anorexogenic agent- stops feeding mechanisms)

Front 33

What is B-Endorphin?

Back 33

-pain
-immune system modulator

Front 34

What 3 hormones are involved in immune function?

Back 34

-prolactin
-MSH
-B-endorphin

Front 35

What is the posterior pituitary composed of?

Back 35

-neuronal tissue

Front 36

Where does the pituitary gland sit?

Back 36

sella turcica

Front 37

What 2 hormones are stored in the posterior pituitary?

Back 37

-vasopressin
-oxytocin

Front 38

There is direct communication between hypothalamus and _____

Back 38

posterior pituitary

Front 39

There is not direct communication between hypothalamus and _____

Back 39

anterior pituitary

Front 40

What does the hypothalamus produce?

Back 40

RH and IH that regulate anterior pituitary hormone production and secretion

Front 41

Every hormone in the anterior pituitary has what?

Back 41

RH and IH (ex. GHRH)

Front 42

What is communication between the anterior and posterior pituitary via?

Back 42

the hypothalmo-hypophysial portal system (no direct cell-cell system)

Front 43

What is GH involved with?

Back 43

only 2 glands in negative feedback system (whereas usually there are 3)

Front 44

What is lacking with GH?

Back 44

a target gland

Front 45

What are the mosts common cells of the posterior pituitary?

Back 45

glial cells

Front 46

Where are the 2 hormones stored in the posterior pituitary produced?

Back 46

in the hypothalamus

Front 47

What does the supraoptic nucleus of the hypothalamus produce?

Back 47

vasopressin (ADH)

Front 48

What does the paraventricular nucleus of the hypothalamus produce?

Back 48

oxytocin

Front 49

The soma of the supraoptic nucleus and paraventricular nucleus are found in the hypothalamus but what do they have?

Back 49

long fibers that extend into the posterior pituitary

Front 50

How does oxytocin cause milk release?

Back 50

stimulates the myoepithelial tissue (have muscle like functions and found surrounding the follicles)

Front 51

Does oxytocin have anything to do with milk production?

Back 51

NO (without oxytocin, milk will still be produced but not released)

Front 52

What does the suckling action of the infant do?

Back 52

will stimulate nerve endings in the nipple to send messages to the brain to release oxytocin

Front 53

What are 4 functions of oxytocin?

Back 53

-milk release
-uterine contractions
-sperm motility
-regulation of feeding mechanism

Front 54

Where are uterine contractions seen?

Back 54

-in menses (menstrual portion of the menstrual cycle) to slough off the lining
-in parturition/birthing to expel fetus

Front 55

Are uterine contractions directly due to oxytocin?

Back 55

-no
-unclear as to whether or not contractions may be partly due to PGF-2alpha (prostaglandin)

Front 56

What is the action of ibuprofen?

Back 56

-antagonizes PGF-2alpha, so if patient is having sever spasms during menses, ibuprofen will reduce the spasms/pain

Front 57

Which does the tail portion of the sperm have a lot of?

Back 57

mitochondria (need ENERGY to propel sperm forward)

Front 58

What does the head portion of the sperm have?

Back 58

nucleus containing half of the complement of the chromosome (1N or haploid)

Front 59

What does the acrosomal body of the head portion of the sperm have?

Back 59

hydrolytic/digestive enzymes to digest membrane of ovum and enter

Front 60

If sperm lacks tail, can fertilization still occur? How?

Back 60

Yes, because of oxytocin (not all the time though)
-during sexual intercourse, hypothalamus of the female releases oxytocin which acts as a vaccuum to pull sperm to the fallopian tubes

Front 61

What is found in high numbers in anorexic individuals?

Back 61

oxytocin

Front 62

High levels of oxytocin may cause what?

Back 62

autism
-very early report, still unclear

Front 63

What is vasopressin (ADH) produced by?

Back 63

supraoptic nucleus of the hypothalamus

Front 64

What are 3 functions of vasopressin?

Back 64

-water conservation (collecting duct) via cAMP
-mild vasoconstrictor
-implicated in memory in rats

Front 65

Thyroid gland: name origin and development

Back 65

-comes from Greek word meaning "shield"
-in fetus, starts as two glands
-then gland migrates towards anterior surface and becomes one gland

Front 66

What is the middle portion of the thyroid called?

Back 66

isthmus

Front 67

What do you find in the thyroid?

Back 67

-large amounts of follicles with colloid material
-when follicular cells are cuboidal=active
-when follicular cells are columnar=active

Front 68

Where is thyroid hormone stored?

Back 68

in colloid material

Front 69

Per weight, thyroid is ______ tissue

Back 69

most vascularized

Front 70

How long can thyroid stay euthyroid for?

Back 70

3 months (has enough thyroid hormone for 3 months)

Front 71

What is the clearance of iodine of the thyroid greater than?

Back 71

iodine clearance of the kidneys
-very slow, active process

Front 72

What happens in the thyroid gland?

Back 72

iodination of thyronine --> 3,5,3',5' tetraiodothyronin

Front 73

What do the thyroid follicular cells produce?

Back 73

T4 (thyroxine)

Front 74

Where is T4 stored?

Back 74

bound to thyroglobulin within colloidal space of follicles

Front 75

What is T4 deiodinized into?

Back 75

T3 (by deiodinases)

Front 76

What is the easiest way to create a drug for a patient who's hyperthyroid?

Back 76

block deiodination of T4 into T3

Front 77

Which is the active hormone, T3 or T4?

Back 77

T3

Front 78

What does T3 do?

Back 78

-increase BMR (basic metabolic rate)
-at normal levels, induces protein synthesis
-at high levels, causes protein degradation
-neuronal development and function (cretinism)
-increase in cardiac activity

Front 79

What is one form of thyrotoxicosis (hyperthyroidism)?

Back 79

Grave's Disease

Front 80

Grave's Disease

Back 80

-autoimmune disease
-immune attack is on TSH receptor by mimicking the effect of TSH causing excessive T4 production by thyroid gland

Front 81

What will appear on a blood test in Grave's Disease?

Back 81

-TSH and TSH-RH will both be low
-T4 will be high

Front 82

What will appear on a blood test in hypothyroidism?

Back 82

-T4 levels will be low
-TSH-RH and TSH will be high (b/c negative feedback is not working)

Front 83

What is the most common reason for hypothyroidism?

Back 83

iodine insufficiency
-treatment would be to give patient iodine

Front 84

What can occur in both hyper and hypoactive thyroid conditions?

Back 84

goiter (enlargement/hypertrophy of the thyroid gland)

Front 85

Where are parathyroid glands found and how many are there?

Back 85

embedded in the thyroid gland
-usually 2 glands, can be 3-4

Front 86

What is the release of PTH extremely sensitive to?

Back 86

levels of blood calcium

Front 87

What is found between the follicular cells and what do they produce?

Back 87

-C-cells
-produce calcitonin

Front 88

What does calcitonin do?

Back 88

-decreases plasma calcium levels by depositing calcium in bone tissues (resulting in increase in bone mineral density)

Front 89

What is the function of BOTH calcitonin and PTH?

Back 89

-maintain normal plasma calcium levels
-induce absorption of calcium by intestine and reabsorption by the kidneys

Front 90

Where is the bulk of calcium found?

Back 90

-bound to proteins or other compounds (if bound=inactive)

Front 91

What does PTH do?

Back 91

-increases plasma calcium levels by inducing resorption of bone tissues (resulting in a decrease of bone mineral density)
-also involved in Vitamin D production (calcitonin has no effect on Vitamin D production)

Front 92

Calcitonin therapy and osteoporosis

Back 92

-derived from salmon
-about 20 times more potent than human calcitonin

Front 93

What is the best therapy (drug) for osteoporosis?

Back 93

PTH (Teriparatide)
-cannot be used for more than 2 years, must stop at this point and treat with other drugs

Front 94

What are 2 easy ways to reduce risk for osteoporosis?

Back 94

-diet
-weight-bearing exercises

Front 95

Biphosphonates

Back 95

-i.e. Fosamax
-has to be taken first thing in the morning, person must remain sitting upright for 30 minutes after taking it
-side effects: intestinal issues, jaw fractures

Front 96

SERM

Back 96

-selective estrogen receptor modulators
-compounds that mimic estrogen
-Raloxifene (problem is it causes hot flashes and potentially blood clots)