endocrinology- I Flashcards
(133 cards)
1
Q
definition
hormone
A
chemical messengers produced by endocrine glands
2
Q
hormones are produced by
A
endocrine glands
3
Q
endocrine glands
A
ductless
4
Q
hormones are released
A
into circulation and travel to target tissues where after binding to specific receptors
they exert specific effect
5
Q
endocrine glands
definition
A
no ducts
- -release hormones into tissue fluids
- -have dense capillary networks to distribute hormones
- -intracellular effects, alter target cell metabolism
6
Q
Exocrine glands
definition
A
- -ducts carry secretion to a surface or organ cavity
- -extracellular effects (food digestion)
7
Q
steroids
A
–all steroids are metabolites of cholesterol
8
Q
steroids are
A
hydrophobic
9
Q
most steroid hormones have
A
specific binding protein in the plasma
e.g. SSBG, transcortin
10
Q
Steroids bind
A
specific nuclear receptors
11
Q
example of progestins
A
progesterone
12
Q
progesterone
A
main sex steroid in the second half of the menstrual cycle
and pregnancy
13
Q
progesterone maintains
A
pregnancy
14
Q
mineralocorticoids
A
aldosterone
Na+ retention
15
Q
glucocorticoids
A
cortisol
INCREASE glucose
16
Q
dihydroxy Vit D
calcitriol
A
not a steroid
acts as nuclear receptor Ca2+ absorbed
17
Q
androgens
A
testosterone
main circulating male sex steroid
penis growth, 2nd sex char, male behavior, libido
18
Q
testosterone converted in target cells to
A
estradiol
or
5 alpha dihydrotestisterone
19
Q
deficiency of
estradiol
or
5 alpha dihydrotestisterone
A
born with ambiguous genitalia
despite XY
possible sex reveral at puberty
male born with few/no androgen receptors
20
Q
estrogen
A
18C
estradiol
estriol
21
Q
estradiol
A
menstrual cycle
22
Q
estriol
A
late in pregnancy
uterus growth
secondary sex characteristics
female behavior, libido
23
Q
protein and polypeptide hormones
A
have primary amino acid structure
24
Q
polypeptide hormones
A
have less amino acids than protein hormones
25
examples of protein hormones
1. insulin
2. growth hormone
3. follicle-stimulation hormone
4. glycoproteins
26
glycoproteins
LH
FSH
TSH
27
peptide hormone...
anti-diuretic hormone
oxytocin
GnRH
28
for each receptor sites on plasma membranes..
hormone binds and leads to a cascade of events in cell and ultimately an effect
29
amine hormones
have NH2 group at end of molecule synthesized from single amino-acids
30
amine hormones act
at plasma membrane receptor
e.g catecholamines
31
amine hormones ex
1. norepinephrine
2. epinephrine
3. melatonin
32
eicosanoids
prostaglandins
33
hypersecretion
endocrine secretion
| Too much
34
hyposecretion
endocrine secretion
| too little
35
endocrine diseases
1. hypersecretion
2. absence/ nonfunctioning receptors
3. hyposecretion
36
endocrine organs
1. pineal gland
2. hypothalamus
3. pituitary gland
4. thyroid gland
5. thymus
6. adrenal gland
7. parathyroid gland
8. gonads
37
pineal gland
found in the brain
38
pituitary gland
hypophysis
39
pituitary gland is suspended
from hypothalamus by stalk (infundibulum)
40
location and size of pituitary gland
housed in sella turcica of sphenoid bone
1.3 cm diameter
41
adenohypophysis
anterior pituitary
arises from hypophyseal pouch
42
hypophyseal pouch
out growth of pharynx
43
neurohypophysis
arises from brain
44
pituitary gland sits
in hole called sella turcica
| turkish saddle
45
pituitary gland is called
"master gland"
of endocrine system
46
anterior pituitary
1. TSH
2. ACTH
3. LH
4. FSH
5. GH
6. prolactin
47
posterior pituitary
1. oxytocin
| 2. vassopressin
48
target gonads
gonadotropin
49
FSH
follicle stimulating hormone
50
LH
luteinizing hormone
51
TSH
thyroid stimulating hormone
thyrotropin
52
ACTCH
adrenocorticotropic hormone
corticotropin
53
PRL
prolactin
54
GH
growth hormone
somatotropin
55
pars intermedia
--present in fetus, absent in adult
--remnant cells
--produce MSH
56
Remnant cells
produce POMC
(pro-opiomelanocortin)
processed into ACTH and endorphins
57
MSH in animals influences
pigmentation of skin, hair, or feathers
58
MSH
no present/functioning in human pituitary but present in skin
59
hypothalamus
"master gland"
neuroendocrine organ
60
hypothalamus synthesizes
OT
| ADH
61
hypothalamus controls
the release of hormones at the anterior pituitary gland
62
hypothalamus secretes
releasing factors or inhibiting factors
63
blood goes to
anterior pituitary from hypothalamus
64
thyroid
found on either side of trachea
65
thyroid hormones produced by
thyroid epithelial cells from thyroglobulin
66
thyroid hormones
T4 T3
increases BMR
Increases cell oxidation
Increases heat generation (uncoupling)
growth and development
67
thyroid produces...
calcitonin by C cells
Decreases Ca2+ in bloodstream
68
parathyroid glands
found embedded in the thyroid tissue
69
parathyroid glands produce
parathyroid hormone
- -polypeptide
- -increase Ca2+ in bloodstream
70
thymus
produces thymosins and other hormones
71
Atria produce
atrial natriuretic factor or peptide
ANF or ANP
72
ventricles brain
natiuretic factor
or peptide
BNF or BNP
73
Na+ balance in body..
indirectly BP regulation
74
adrenal glands found
superior to the kidneys in most mammalian species
involved with stress response
75
adrenal cortex
outer layer
responsible for the synthesis of
1. aldosterone
2. cortisol
3. sex steroids
76
adrenal medulla
inner layer
responsible for secretion of
epinephrine
norepinephrine
involved in emergency reactions
77
stomach
releases gastrin from G-cells
78
duodenum releases
cholecystokinin (CCK)
79
duodenum goes
to gallbladder to release bile
80
duodenum goes to pancreas
to release enzymes to break down protein
81
duodenum releases secretin
goes to pancreas to release HCO3- to neutralize low pH
82
pancreas releases
insulin
glucagon
somatostatin
pancreatic polypeptide
83
fat cells
leptin
84
kidney
Renin
| erythropoietin
85
gonads
ovaries
| testes
86
ovaries produce
estrogen (estradiol)
progesterone
inhibin
relaxin
87
testes produce
testosterone
inhibin
88
placenta
rich source of hormones
89
human chorionic gonadotropin
| hCG
maintains pregnancy
acts like LH-basis for home pregnancy test
90
human placental lactogen
| HPL
acts like growth hormone
91
progesterone
maintains pregnancy
92
estrogen
estriol
93
feeback mechanisms
regulate hormone concentrations
94
negative feedback loop
| LH
LH to blood
- causes testosterone production INCREASE
- testosterone enters the blood (brain): inhibits release of LH DECREASE
95
positive feedback loop
very few hormonal systems exist
96
hypothalamus is critical
to life controlling reproduction, body temp, stress response, eating, drinking
97
pituitary gland
made up of anterior/posterior
98
adrenocorticotropic hormone
ACTH
produced from proopiomelatocortin(POCMC)
released into blood --> adrenal cortex --> release glucocorticoids
cortisol is major INCREASE
99
-tropin
exerting an action or stimulating growth
100
glucocorticoids exert
a negative feedback effect on
| ACTH release at the anterior pituitary
101
Luteinizing hormone
| LH
glycoprotein to blood
102
LH action on females
causes produces ovulation
stimulates CL to produce progesterone (maintain pregnancy) and estrogen
103
LH action on
| males
stimulates Leydig or intestitial cells in testis --> testosterone INCREASES leads to male characteristics
beard, body hair, muscling, balding
104
testosterone or progesterone exert
a negative feedback
105
luteinizing
causes formation of the corpus luteum CL
106
Follicle-stimulating hormone
FSH
glycoprotein
2nd gonadotropin
107
FSH...
ACTIONS on gonads
female STIMULATES FOLLICLES
causes estrogen release (by FOLLICLES in ovaries)
stimulates production of inhibin which inhibits FSH release
108
FSH males stimulates
spermatogenesis
109
Thyroid stimulating hormone
TSH
Thyrotropin
110
TSH
glycoprotein
acts on thyroid gland
- -production and release of thyroid hormones
- -growth
--thyroxine and triiodothyronine INCREASE
111
thyroid hormones have
negative feedback effct on the TSH
112
growth hormone
GH
protein
called somatotropin
muscle size INCREASE and bone accretion
113
GH acts
through IGF-1 on growth
114
excess growth hormone
in children leads to gigantism
115
excess GH in adults
acromegaly
| only affects areas that can still grown
hands, head, feat
116
deficiency of GH
hypopituitary dwarf
treated with human growth hormone
117
laron dwarf
lacking GH receptor
118
prolactin
protein
lactation
- -mammary gland development
- -milk production
119
melanocytes
cells in skin that contain melanin changes skin color
120
brown/black pigment
eumelanin
121
red/orange
pheomelanin
122
hormones released from the posterior pituitary
produced in hypothalamus
123
neurosecretory neurons
nerve cell bodies in the hypothalamus.
| modified axons to PP
124
neurosecretory neurons end up with
neurosecretory terminals
125
ADH or vasopressin
9 amino acids
126
ADH or vasopressin
acts on
distal convoluted tubule and collectind ducts
127
ADH vasopressin
does what
INCREASE permeability to H2O
no feedback mechanism
128
oxytocin
| size
9 amino acid
| peptide
129
Oxytocin...
pitocin is a sythetic oxytocin analog
130
Oxytocin actions
INCREASE smooth muscle contraction in
| uterus, vagina, mammary glands
131
Milk ejection
Hypo --> PP --> oxytocin --> milk ejection
132
Milk production
Hypo --> AP --> prolactin --> milk production
133
thyrotropin releasing hormone
TRH
released by hypothalamic neurons into blood
TSH secretion INCREASED
negative feedback
prolactin secretion INCREASE
