Physiological regulation Flashcards
1
Q
what are two methods for cells, tissues, and organs regulation
A
extrinsic and intrinsic
2
Q
how does physiologic regulation take place
A
through communication between structures using chemical signals
3
Q
what are the two extrinsic regulatory systems of the body
A
nervous and endocrine system
4
Q
what are the two mechanisms of intercellular communication
A
direct and indirect
5
Q
direct intercellular communication
A
when ions and molecules pass directly from the cytoplasm of one cell to another
6
Q
indirect intercellular communication
A
ligands released from one cell bind to a receptor on another
7
Q
four functional classifications of chemical messangers
A
- paracrine
- autocrine
- neurotransmitters
- hormones
8
Q
paracrine
A
a ligand secreted into the ECF which travels by diffusion and binds to a neighboring cell
9
Q
autocrine
A
a ligand secreted by a cell into the ECF that binds on its own receptors
10
Q
neurotransmitters
A
ligands secreted from neurons, into a synapse, and bind to a post synaptic receptor
11
Q
hormones
A
ligands secreted into blood by endocrine cells, transported by the blood to a target cell receptor
12
Q
what are the five structural classifications of chemical messangers
A
- amino acids
- amines
- steroids
- proteins
- eicosanoids
13
Q
what is the primary function of amino acid messangers
A
neurotransmitters in the CNS
14
Q
what are four common specific amino acid messangers
A
- glutamate
- aspartate
- glycine
- GABA
15
Q
what are four groups of amine ligands
A
- catecholamines
- thyroid hormones
- serotonin
- histamine
16
Q
what amino acid are catecholamines derived from
A
tyrosine
17
Q
what are three catecholamines
A
- epinephrine
- norepinephrine
- dopamine
18
Q
epinephrine
A
a catecholamine secreted by the adrenal medulla
19
Q
norepinephrine
A
a catecholamine that acts as a CNS and PNS neurotransmitter and as a hormone secreted from the adrenal medulla
20
Q
dopamine
A
a catecholamine CNS neurotransmitter
21
Q
what is the difference between a neurotransmitter and hormone
A
where they are found
22
Q
what amino acid are T1 an T2 derived from
A
tyrosine
23
Q
what tyoe of ligand are thyroid hormones
A
amines
24
Q
serotonin
A
an amine neurotransmitter derived from tryptophan
25
histamine
a paracrine amine ligand derived from histadine
26
where are steroid ligands derived from
cholesterol
27
what are 5 types of steroid ligand
1. glucocorticoids
2. mineralocorticoids
3. androgens
4. estrogens
5. progestines
28
what is the main glucocorticoid
cortisol
29
what is the primary mineralocorticoid
aldosterone
30
what is the primary androgen
testosterone
31
what is the primary estrogen
estradiol
32
what is the primary progestin
progesterone
33
what type of ligand has the largest number of chemical messangers
protein
34
eicosanoids
paracrine ligands derived from arachidonic acid produced by virtually all cels of the body
35
Vmax
the maximum rate at which a ligand will bind to its receptor
36
what influences Vmax
the number of ligands up to Vmax, then only increasing the proteins will change anything
37
KM
the concentration of a ligand that will elict a reaction rate 1/2 of Vmax
38
what is KM a measure of
affinity of a ligand for its receptor
39
what ligands are transported in blood
hormones
40
what three ligands are transported by diffusion
autocrines, paracrines, neurotransmitters
41
how are hormones transported in blood
some can dissolvle in blood, some need a protein carrier
42
T/F receptors show specificity for a messanger
true
43
T/F most receptor/ligand binding is permanent
false, it is temporary and reversible
44
How many different receptors can a ligand bind to
usually more than one, but different receptors have a different affinity for a single messanger
45
T/F most target cells have receptors for only one ligand
false, most have receptors for many different ligands
46
at a subsaturation point for different ligands, which will bind more readily to the receptor
the ligand with the highest affinity
47
how can you have two different ligands with the same Vmax but differet KM
KM is based on affinity between the receptor ligand, Vmax is a measure of saturation point.
48
what is the relationship between KM and affinity
the ligand with the highest affinity has a lower KM
49
what happens to Vmax if the number of receptor proteins is doubled
the Vmax will also double
50
what three factors determine the magnitude of cell response
1. messanger concentration
2. number of receptors on target cell
3. affinity between receptor and ligand
51
receptor agonist
an exogenous compound that binds to a receptor and causes a normal biologic response
52
receptor antagonist
an exogenous compound that binds to a receptor and produces no response
53
dopamine
54
epinephrine
55
norepinephrine
56
what two types of ligands can pass the cell membrane without a carrier
1. steroid hormones
2. T3 and T4
57
where do lipid soluble (lipoholic) ligands have their receptors
inside the cell
58
what are three types of ligands that can't cross the cell membrane
1. proteins
2. amino acids
3. amines (except thyroid hormone)
59
where are the receptors for non-lipid soluble (lipophobic) ligands found
on the cell memrbane
60
how do ligands with intracellular receptors create a response in the cell
* hormones bind to receptor
* hormone/receptor complex binds to DNA at a promotor
* allow for gene expression and protein synthesis
* new protein produces a response
61
what are two plasma membrane receptors that a ligand will bind with
1. ion channels
2. enzymes
62
what is a fast response receptor? give two examples
when the plasma membrane receptor and effector are the same protein
nicotinic receptor and tyrosine kinase receptor
63
nicotinic receptor
a fast ion channel receptor found on the PM of in muscle and nervous tissue
64
what does a nicotinic receptor do on skeletal muscle
opens ion channels, allowing Na and K into the cell, which depolarizes the cell membrane
65
what is a calcium channel?
a fast ion channel found on the cell membrane
66
what are 4 thinsg that happens when calcium channels open
1. the PM depolarizes
2. muscles contract
3. secreton
4. calcium binds to calmodulin
67
what happens when calcium binds to calmodulin
protein kinase is formed, which phosphorylates protein to cause a response in the cell
68
tyrosine kinase receptor
a fast PM enzyme that phosphorylates tyrosine with ATP to make PTP and cause a cellular response
69
what are G protein linked receptors
a receptor that needs to use an intermediary G protein to couple with intracellular effectors and produce a response
70
T/F G protein effectors are always enzymes
false, they can be ion channels too
71
slow response receptors
receptors that are not bound to their effector and need an intermediary G protein to for a response
72
two examples of slow response receptors
1. muscarinic receptor
2. adrenergic receptor
73
five step process for G linked receptor interactions
1. a receptor is inactive with a GDP bound to it
2. ligand binding releases GDP
3. GTP is phosphylated to GTP
4. GTP alpha and beta parts disassociated
5. one of the parts binds with the effector
74
what are the 3 parts of a G protein
1. alpha
2. beta
3. y
75
six steps for how adenylate cyclase produces a cellular response
1. catecholamines bind to adrenergic receptor
2. receptor releases GDP
3. GTP binds to adenylate cyclase
4. GTP + ATP + adenylate cyclase produces cAMP
5. cAMP activates protein kinase
6. protein is phosphorylated
76
what is the second messanger in the adenylate cyclase reaction? phospholipase C?
cAMP
IP3 and DAG
77
what is the process by which phospholipase C produces IP3 and DAG
1. epinephrine binds to adrenergic receptors
2. receptor release GDP
3. GDP --\> GTP
4. GTP binds with phospholipase C
5. IP3 and DAG are produced
78
what is the action of IP3 produced by phospholipase C in the cell? what process is started
IP3 binds to ion channels on the smooth ER which release Ca, which binds to calmodulin, allowing for the production of protein kinase
79
what is the action of DAG in the cell
activation of protein kinase C and phosphorlyation of protein
80
what is signal amplification in reference to cyclic AMP
the concept that a single ligand can produce several reactions inside the cell
81
what are the primary endocrine organs (9)
1. hypothalamus
2. pituitary
3. pineal
4. thyroid
5. parathyroid
6. thymus
7. adrenal
8. pancreas
9. gonads
82
primary endocrine organ
an organ whose only job is to secrete or store ligands
83
secondary endocrine organs (6)
1. heart
2. liver
3. stomach
4. small intestine
5. kidney
6. skin
84
T/F together the hypothalamus and pituitary regulate almost every body system
true
85
where do most hypothalamic hormones bind
to receptors on the pituitary
86
adenohypophysis
the anterior lobe of the pituitary
87
neurohypophysis
posterior lobe of the pituitary
88
what two hormones are secreted from the posterior pituitary
1. oxytocin
2. ADH
89
describe the process for the posterior pituitary to secrete hormones
1. ADH and oxytocin are made in the hypothalamus
2. hormones are packed and sent to the neural endings in the pituitary
3. when stimulated the hypothalamic neurons release hormones into the blood
90
describe the interaction between the hypothalamus and anterior pituitary to secrete hormones
1. neurosecretory cells in the hypothalamus produce releasing hormones
2. releasing hormones are secreted in to the hypothalamic-pituitary portal system
3. the portal system carries releasing hormones to the anterior pituitary and stimulates the secretion of trophic hormones
91
what two things regulate the secrete of anterior pituitary hormones
1. negative feed back from the trophic hormones
2. negative feed back from organ stimulated by pituitary hormones
92
how does caffiene influence energy production
it inhibits the action of phosphodiesterase, stopping it from breaking down cAMP into AMP to stop protein phosphorylation
93
what are two methods of regulating a hormonal response once it has started
changing the production of the stimulating ligand
changing the rate of clearance
94
what are the hormones released by the hypothalamus
1. PRH
2. PIH
3. TRH
4. CRH
5. GRHR
6. GHIH
7. GnRH
95
PRH/PIH
prolaction releasing/inhibiting hormone
96
TRH
thyroid releasing hormone
97
CRH
corticosteroid releasing hormone
98
GHRH/GHIH
growth hormone releasing/inhibiting hormone
99
GnRh
gonadotropin releasing hormone
100
what are the hormones released by the anterior pituitary
1. prolactin
2. TSH
3. ACTH
4. GH
5. LH
6. FSH
101
TSH
thyroid stimulating hormone
102
ACTH
adrendocorticotropic hormone
103
LH
lutenizing hormone
104
FSH
follicle stimulating hormone
105
what are three ways blood hormone levels are controlled
1. secretion rate
2. carrier protein binding
3. clearance rate
106
how is secretion rate regulated
negative feedback through end product inhibition
107
how do carrier proteins regulate blood hormone levels
lipoholic hormones can only have a concentration equal to the concentration of carrier proteins
108
what degrades hormones? are intracellular or extracellular hormones more quickly broken down
enzymes
lipophobic (extracellular) are broken down more quickly
109
four types of hormone interaction
1. antagonistic
2. addittive
3. synergistic
4. permissive
110
antagonistic hormone interaction (example)
two hormones that have opposite effects (insulin and glucagon)
111
additive hormone effects (example)
two hormones have the same effect through different mechanisms, so the effect is the sum of the individual effects (cortisol and GH on lipolysis)
112
synergistic hormone effects (example)
two hormones with the same action but the combination of their effect is greater than there individual sums
(GH and insulin)
113
permissive hormone effects 9example)
when one hormone needs another to do its function (estradiol produces receptors for progeterone)
114
what are the four main hypothalamic-pituitary axes
1. tthyroid
2. adrenal
3. liver
4. gonads
115
name and describe the axis that produces thyroid hormone
thyroid axis
1. TRH is secreted by the hypothalamus into the blood
2. TRH stimulates the anterior pituitary to produce TSH
3. TSH released into the blood acts on the thyroid to produce TH
116
name and describe the axis that produces cortisol
adrenal axis
1. CRH is produced in the hypothalamus and released into the blood
2. CRH stimulates anterior pituitary produce of ACTH
3. ACTH acts on the adrenal cortex to produce cortisol
117
name and describe the axis that produces GH
growth hormone axis
1. GHRH is produced in the hypothalamus
2. GHRH stimulates production of GH in the anterior pituitary
3. GH acts on somatic cells to produce growth
4. GH also acts on the liver to produce IGF
118
what hormone produced in the hypothalamus inhibits production of GH in the anterior pituitary
somatostatin
119
describe the gonadal axis
1. GnRH is produced in the hypothalamus
2. GnRH stimulates the production of LH and FSH in the anterior pituitary
3. LH and FSH stimulate the production of androgens and estrogens from the gonads
120
what hormones are produced in the anterior pituitary in response to GnRH?
what hormones will GnRH produce?
FSH and LH
androgens and estrogens
121
what type of receptor is a muscarinic receptor?
what does it do?
slow response receptor bond it an ion channel
* acetylcholine from a neuron binds to muscarinic receptors on smooth muscle or another neuron,
* GDP is released and phosphorylated into GTP
* GTP binds to an ion channel to allow flux
122
what type of receptor is a nicotinic receptor
what does it do?
a fast ion channel
when bound with acetylcholine nicotinic receptors open and allow flux of ions
123
what type of receptor is tyrosine kinase?
what does it do?
a fast response enzyme
when bound with a protein ligand it allows for the production of PTP, which affects intracellular change
124
describe an example of signal amplification
1. catecholamine bind to adrenergic receptor
2. receptor produces several G proteins
3. each G protein activates one adenylate cylase
4. each adenylate cyclase produces several cAMP
5. each cAMP activates several protein kinases
6. each protein kinase phosphorylates several proteins
