Hormones Biochem 1-3 Flashcards
1
Q
3 physiological communication systems of the body
A
Nervous, endocrine, immune system
2
Q
Mediates communication of nervous system
A
Neurotransmitter
3
Q
Messenger of the endocrine system
A
Hormones
4
Q
Messenger of the immune system
A
Cytokines
5
Q
Hormones acting on adjacent cells
A
Paracrine
6
Q
Hormones acting on cells in which they were synthesized
A
Autocrine
7
Q
Hormones with receptors in the membrane
A
Protein (hydrophilic) hormones
8
Q
Hormones with receptors located inside the cell
A
Steriod (lipophilic) hormones
9
Q
What is the binding of hormone to specific receptors stimulating a cascade of reactions called?
A
Signal transduction
10
Q
Types of hydrophilic hormone receptors
A
G-protein-coupled receptors, Jak/STAT kinase cascade
11
Q
Effect of protein hormone binding to GPCR
A
GDP displaced by GTP. GTP is then hydrolyzed to GDP by the intrinsic GTPase activity
12
Q
Effector of Gs
A
Adenylyl Cyclase stimulated
13
Q
Effector of Gi
A
Adenylyl Cyclase inhibited
14
Q
Effector of Gq
A
Phospholipase C stimulated
15
Q
What does adenylyl cyclase convert?
A
ATP to cAMP
16
Q
What does cAMP stimulate?
A
protein kinase A
17
Q
What does activated protein kinase A do?
A
Phosphorylates proteins
18
Q
Stimulates membrane bound guanylyl cyclase
A
Atrial natriuretic factor
19
Q
Stimulates souble guanylyl cyclase
A
NO
20
Q
What does cGMP stimulate?
A
Protein Kinase G
21
Q
What does protein kinase G do?
A
Phosphorylates smooth muscle proteins to relax smooth muscle and vasodilate
22
Q
Cascade of activated Gq protein
A
Phospholipase C stimulated, PIP2 cleaved into DAG and IP3
23
Q
Action of insulin binding to intracellular kinase cascade
A
Receptor is phosphorylated, Insulin receptor substrates are phosphorylated, this results in the stimulation of a number of different kinases
24
Q
Receptors in the cytosol bound to heat shock proteins
A
Cytosolic receptors
25
2 types of lipophilice hormone receptors
Cytosolic and Nuclear receptors
26
Pathway of cytosolic receptors
Hormone binds in cytosol, HSPs displaced, allowing the complex to migrate into the nucleus. Complex binds to hormone response element, which affects the transcriptions of the gene either negatively or positively
27
Pathway of nuclear receptors
Binding of hormones occurs in the nucleus, complex bind to HRE and affects the transcription of the gene
28
Master control center of endocrine system
Hypothalamus
29
What hormones from the pituitary use the Jak/STAT cascade?
GH and prolactin
30
What hormones from the pituitary use GPCR?
TSH, FSH, LH (use Gs/ adenylyl cyclase stimulated cAMP pathway)
31
What determines the biological activity of the hormone?
the beta subunit
32
What hormones are derived from POMC?
ACTH, MSH, Lipotropin, endrophins
33
hormone that decreases pain perception and causes euphoria
Endorphins
34
Where are the hormones produced in the hypothalamus stored?
Posterior pituitary
35
Principle hormones of the posterior pituitary
Oxytocin and vasopressin
36
Carrier proteins for oxytocin and vasopressin
Neurophysins
37
Main regulator hormone of body fluid osmolarity
ADH
38
Hormone that stimulates lactation and uterine contraction during delivery
Oxytocin
39
Oxidizes Iodide to I+
thyroperoxidase (found only in thyroid tissue)
40
How are T3 and T4 released into circulation?
Lysosomal proteases degrade the thyroglobulin to release amino acids and T3/T4
41
Carrier proteins for thyroid hormones
Thyroxin binding globulin and thyroxin binding prealbumin
42
What increases the half life of thyroid homrones?
Binding of hormones to carrier proteins
43
Converts T4 into T3
Deiodinase
44
What do T3 receptors do to T3?
Inactivate it
45
What does parathyroid hormone activate?
Adenylyl cyclase, stimulating bone reabsoprtion, increasing serum Ca2+ and depressing plasma Pi, Pi secretion stimulated in the kidney
46
Major form of vitamin D in the blood
25(OH)-D3
47
Hypocalcemia results in marked increases of what?
1 alpha-hydroxylase activity
48
Active biological form of vitamin D
1,25 (OH)2-D3
49
Where is calcitonin produced?
C cells of thyroid
50
Effect of calcitonin
Lowers ciruclating Ca2+ and Pi levels, increases Ca2+ excretion in the urine
51
Hormone secreted by cardiac muscle when sodium chloride intake is increased and when the volume of the extracellular fliud expands
Atrial Natriuretic Peptide
52
Effects of ANP
natriuresis, diuresis, systemic vasodilation, inhibition of aldosterone secretion
53
What do the pacreatic beta cells produce?
Insulin
54
Effects of insulin
Increases glucose uptake/utilization, increases lipogenesis, general anabolic effects
55
What type of receptor does insulin bind to?
Tyrosine Kinase receptor
56
What do alpha cells of pancreas produce?
Glucagon
57
Effect of glucagon?
increases lipid mobilization and glycogenolysis to increase blood glucose levels
58
What do the f cells of the pancrease produce?
Pancreatic polypeptide
59
Function of pancreatic polypeptide
Increase glycogenolysis, regulation of GI activity
60
What do delt cells of pancrease produce?
Somatostatin
61
Function of delt cells
inhibits glucagon and insulin secretion
62
What is NE and Epi derived from?
Tyrosine
63
What receptors does NE bind to?
Beta2 adrenergic
64
What type of receptor does Epi bind to?
All catecholamine receptors
65
Converts NE into Epi
PNMT (Phenylethanolamine-N-Methyltransferase)
66
Where is PNMT found?
Brain and adrenal medulla (glucocorticoids stimulate PNMT in medulla)
67
Adrenergic receptor coupled to Gq
Alpha 1, results in increased Ca and smooth muscle contraction
68
Adrenergic receptor coupled to Gi
Alpha 2, decreases neurotransmitter release and decreases cAMP activity resulting in smooth muscle contraction
69
Adrenergic receptor coupled to Gs
Beta, increases intracellular cAMP, which results in: heart muscle contraction, smooth muscle relaxation, glycogenolysis
70
Where are endocrine hormones secreted in the GI system?
Mucosal glands
71
Appetite stimulation hormone
Ghrelin
72
Hormone that stimulates acid and pepsin secretion
Gastrin
73
Potentiates glucose-dependent insulin secretion and inhibits glucagon secretion
Glucagon-like peptide 1
74
Stimulates the release of HCO3 and H2O
Secretin
75
Increases secretion of digestive enzymes from pancreas
Cholecystokinin
76
Relaxes GI, inhibits acid and pepsin secretion
Vasoactive intestinal peptide
77
Suppresses glucose-induced insulin secretion
Pancreatic polypeptide
78
Controls feeding behavior and energy homeostasis
Neuropeptide Tyrosine
79
Regulates overall body weight by limiting food intake, increases energy expenditure
Leptin
80
Increases insulin sensitivity and fatty acid oxidation
Adiponectin
81
Induces insulin resistance
Resistin
82
Steroids produced in adrenal cortex
Cortisol, aldosterone, androgans, DHEA, andorstenedione
83
Steroids produced in testis
Testosterone
84
Steriods produced in ovaries
Estrogens (estradiol, estriol, estrone), progesterone
85
What are steriod hormones derived from?
Cholesterol
86
First step in making steriod from cholesterol
Removal of side chain
87
Rate limiting step of Pregnenolone synthesis
STAR transports cholesterol to mitochondria, is ACTH dependent in adrenal
88
3 main tissue regions of adrenal cortex
Zona: glomerulosa, fasciculata, reticularis
89
Regulates body levels of sodium and potassium
Mineralocorticoid
90
Regulates carbohydrate metabolism
Glucocorticoid
91
Action is similar to that of steriods produced by the male gonads
Androgens
92
Enzyme only found in the zona glomerulosa
Aldosterone synthase
93
Where does cortisol synthesis occur?
Zona fasciculata
94
Where does androgen synthesis occur?
Zona reticularis
95
Liver derived glycoprotein that binds to the majority of cortisol
Corticosteriod binding alpha2-globulin
96
What cells form testosterone?
Leydig cells
97
What is more potent that testosterone?
Dihydrotestosterone
98
Produced in Sertoli cells
Androgen-binding protein, stimulated by testosterone and FSH
99
Pathway to stimulate testosterone synthesis
GnRH from hypothalamus, stimulates anterior pituitary, LH made and stimulates testis cells for testosterone production, FSH stimulates spermatogenesis
100
Main estrogen of ovary stimulated by FSH
17beta-estradiol
101
Regulation of ovulation
Hypothalamus secretes GnRH, stimulating anterior pituitary to secrete FSH, FSH stimulates follical development in the ovary, LH stimulates ovulation
102
Main site of sex hormone binding globulin metabolism
Liver
103
Steriod that maintains pregnancy
Estrogens
104
Mimics action of progesterone
Progestins
105
Steriod with similar activity to LH secreted by the placeta
Chorionic gonadotropin
106
Sterios that acts like prolactin and GH, is secreted by the placenta
Placental lactogen
107
Produced in the ovarian corpus luteum, inhibits myometrial contractions, secretion increases during gestation
Relaxin
108
3 hormones produced by kidneys
Renin; 1,25-dihydroxycholecalciferol; erythropoietin
109
What endocrine organ secretes melatonin?
Pineal gland
110
What cells produce renin?
JG cells
111
What is a substrate for renin?
Angiotensinogen (produced in the liver)
112
Potent vasoconstrictor and a potent stimulator of aldosterone production
Angiotensin II
113
Produced in the skin of mammals from 7-dehydrocholesterol by the action of sunlight
Vitamin-D3, aka cholecalciferol
114
Where is 25-hydroxycholeciferol converted?
Proximal tubules of the kidney
115
Vitamin D deficiency in children
Rickets
116
Facilitates Vitamin D3 formation
PTH
117
What is markedly increased in bolod levels in anemia?
Erythropoietin
118
Where is erythropoietin produced?
Endothelial cells of peritubular capillaries of the renal cortex and the liver
119
Endocrine gland attached to the posterior region of the epithalamus
Pineal gland
120
Hormone that inhibits breast cancer cell growth
Melatonin
121
A large variety of polypeptice growth factors that work on human tissues and cells
Autocoids
122
Result of a reduction in GH levels
Loss of weight and body mass
123
Side effects of hormone replacement therapy
Heart attacks, cancer, breast cancer
