ENDO 1- General endocrinology

Question 1

what does the endocrine system do

Answer 1

provides broadcast regulation of many tissues

Question 2

what is the specificity of the endocrine system due to

Answer 2

receptors

Question 3

what are the 3 things hormones regulate

Answer 3

-maintenance of homeostasis
-growth and differentiation
-reproduction

Question 4

what hormones maintain homeostasis

Answer 4

thyroid hormone, insulin, PTH, vasopressin, aldosterone

Question 5

what hormones participate in growth and differentation

Answer 5

growth hormone, thyroid hormone

Question 6

what hormones participate in reproduction

Answer 6

-LH
-FSH
-Estrogen
- progesterone
-testosterone

Question 7

what are the specialized endocrine glands

Answer 7

-pituitary gland
-thyroid gland
- parathyroid gland
- adrenal gland
- pineal gland

Question 8

what endocrine cells are in the hypothalamus

Answer 8

TRH,CRH

Question 9

what endocrine cells are in the skin

Answer 9

vitamin D

Question 10

what endocrine cells are in the liver

Answer 10

iGF-1

Question 11

what endocrine cells are in the pancreas

Answer 11

insulin and glucagon

Question 12

what endocrine cells are in the kidney

Answer 12

renin, epo, and vitamin D

Question 13

what are the classes of hormones

Answer 13

-proteins and polypeptides
-steroids
- derivatives of tyrosine

Question 14

where are protein and polypeptide hormones found

Answer 14

hypothalamus
-anterior pituitary
-posterior pituitary
-pancreas

Question 15

what is the process of synthesis in protein and polypeptide hormones

Answer 15

synthesized first as a preprohormone
-converted to prohormone
-prohormone is cleaved into the active hormone and inactive fragments

Question 16

are protein and polypeptide hormones made on demand

Answer 16

no they are made early then stored

Question 17

what steroid hormones are synthesized from cholesterol

Answer 17

-cholesterol
- DHEA
-androstenedione
-aldosterone
-cortisol
- testoterone
-estradiol

Question 18

where are steroid hormones from

Answer 18

adrenal cortex, ovaries and testes

Question 19

what type of steroid hormone is cortisol

Answer 19

glucocorticoid

Question 20

what type of steroid hormone is aldosterone

Answer 20

mineralocorticoid

Question 21

are steroid hormones made on demand

Answer 21

yes

Question 22

what are amine hormones derived from

Answer 22

amino acid tyrosine

Question 23

what are examples of amine hormones

Answer 23

thyroid hormone and adrenal medullary neurohormones such as epinephrine and norepinephrine

Question 24

are amine hormones produced on demand

Answer 24

no they are made early

Question 25

how are amine hormones stored

Answer 25

thyroid hormones bind to the protein thyroglobulin -epinephrine and norepinephrine are stored in vesicles and released by exocytosis

Question 26

what makes thyroid hormones an exception to transport across a membrane

Answer 26

the carbon rings make it slightly hydrophobic which allows it to diffuse across the membrane freely and bind to intracellular receptors

Question 27

what do binding proteins do

Answer 27

serve as a reservoir for the hormone and prolong the hormone's half life

Question 28

what type of the hormone is the active form of the hormone

Answer 28

the free or unbound hormone

Question 29

how do the majority of amines peptides, and protein hormones circulate

Answer 29

in their free form

Question 30

how do steroid and thyroid hormones circulate

Answer 30

bound to specific transport proteins

Question 31

what do globulin and albumin bind to

Answer 31

hormones

Question 32

what does thyroid hormone travel in plasma bound to

Answer 32

thyroxine binding globulin (TBG) and transthyretin (TTR) and albumin

Question 33

where are most binding proteins synthesized

Answer 33

in the liver

Question 34

what could changes in liver function do to binding protein levels

Answer 34

could alter them and indirectly affect plasma hormone levels

Question 35

do binding proteins cross the membrane and enter the target cell

Answer 35

no they stay in the blood vessel and it unbinds the hormone which crosses the membrane alone

Question 36

what is the fluctuation in plasma hormone levels due to

Answer 36

hormonal, neural, nutritional and environmental factors

Question 37

what type of hormone is cortisol

Answer 37

tonic

Question 38

when is cortisol the highest

Answer 38

in the early morning

Question 39

what is pulsatile secretion

Answer 39

secreted in pulses

Question 40

what is an example of a hormone that has pulsatile secretion

Answer 40

growth hormone

Question 41

the location of the hormone receptor depends on ___

Answer 41

the chemical properties of the hormone (lipophilic/lipophobic)

Question 42

what does ligand/receptor binding demonstrate

Answer 42

specificity, affinity, and saturation

Question 43

what types of hormones use plasma membrane receptors

Answer 43

polypeptide, protein and amine hormones

Question 44

what are the peptide and protein hormones that use plasma membrane receptors

Answer 44

glucagon, angiotensin, GnRH, SS, GHRH, FSH,LH,TSH,ACTH

Question 45

what are the amino acid hormones that use plasma membrane receptors

Answer 45

epi and NE

Question 46

which type of hormones use nuclear receptors

Answer 46

thyroid and steroid hormones

Question 47

what do hormones that bind to nuclear receptors cause

Answer 47

changes in gene expression, biological response, and protein synthesis

Question 48

which type of receptors elicit a faster response

Answer 48

plasma membrane receptors

Question 49

what are the plasma membrane hormone receptors

Answer 49

-GPCRs - tyrosine kinase: insulin -serine kinase -cytokine: leptin

Question 50

what hormones use Gs coupled receptors

Answer 50

beta adrenergic, calcitonin, ACTH, glucagon, TSH, vasopressin

Question 51

what second messenger do plasma membrane hormone Gs coupled receptors use

Answer 51

cAMP

Question 52

what hormones use Gq coupled receptors

Answer 52

alpha adrenergic, angiotensin II, TRH

Question 53

what second messengers do Gq coupled receptors use

Answer 53

IP3, DAG and Ca2+

Question 54

where are nuclear hormone receptors found

Answer 54

either in cytoplasm or nucleus

Question 55

how do nuclear hormone receptors work (mechanism)

Answer 55

the hormone receptor complex binds to a hormone responsive element in the promoter region of a gene which leads to either activation or repression of transcription and forms new proteins

Question 56

what are the effects of combined actions of hormones

Answer 56

-antagonism -additive -synergistic -permissiveness

Question 57

what is permissiveness

Answer 57

presence of one hormone required to see the max effect of another hormone

Question 58

explain the 5 steps in regulation of thyroid hormone secretion

Answer 58

-stimulus causes the hypothalamus to secrete TRH which acts on the anterior pituitary - thyrotropic cells in the anterior pituitary release TSH - TSH stimulates follicular cells of the thyroid gland to release thyroid hormone - TH stimulates target cells to increase metabolic activities resulting in an increase in basal body temperature - increased body temperature is detected by the hypothalamus and secretion of TRH by the hypothalamus is inhibited. TH also blocks TRH receptors on the thyrotropic cells inhibiting synthesis and release of TSH. both effects indirectly dampen TH production in the thyroid

Question 59

how do endocrine orders occur

Answer 59

when negative feedback loops dont function properly

Question 60

what is a primary disorder

Answer 60

abnormality in the last endocrine organ secreting the hormone leading to either hypo or hyper secretion

Question 61

what are the causes of primary hyposecretion

Answer 61

-partial destruction of the gland - dietary deficiency - enzyme deficiency required for hormone synthesis

Question 62

what is the cause of primary hypersecretion

Answer 62

a tumor in the endocrine gland

Question 63

what are secondary disorders caused by

Answer 63

an abnormality in tropic hormone leading to either hypo or hyper secretion

Question 64

what causes secondary hyposecretion

Answer 64

a lack of sufficient tropic hormone

Question 65

what causes secondary hypersecretion

Answer 65

a tumor either in an endocrine gland that secretes tropic hormone or in non-endocrine tissues that secretes hormones

Question 66

what is another name for secondary hypersecretion

Answer 66

paraneoplastic endocrine syndrome

Question 67

what happens with cortisol in primary hypersecretion

Answer 67

-the adrenal gland is abnormal and secreting excess cortisol. it acts back on the hypothalamus and anterior pituitary and results in decrease CRH from hypothalamus and decrease ACTH from the anterior pituitary

Question 68

what happens with cortisol in secondary hypersecretion

Answer 68

the problem starts with the anterior pituitary that secretes excess ACTH resulting in excess cortisol secretion from the adrenal gland. this acts back on the hypothalamus and anterior pituitary but regulation is inadequate in anterior pituitary but decreases CRH in the hypothalamus

Question 69

what are the diagnostic tests of endocrine function

Answer 69

-plasma hormone levels - autoantibodies -urine hormone or hormone metabolite levels - stimulation tests by administrating of a tropic or stimulating hormone - suppression tests when hyperfunction of an endocrine organ is suspected - measurement of hormone receptor presence, number and affinity - imaging