Endocrinology (1) Flashcards

proof of hormones the system process of Renin-angiotensin-aldosterone system function of angiotensin II inhibitors hormonal system hormone family and its interaction with receptor measuring levels of hormones secretion of hormones regulation of systems

1
Q

secretin - discovered

A

by William Bayliss and Ernest Starling

1st hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

secretin tested - neuronal

A

isolate gut from nervous system by cutting nerves to gut and add acid to duodenum = there was secretion
therefore not neuronal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

secretin tested - chemical and results

A

stop blood flow from gut to general circulation and repeat with acid = no secretion
therefore acid on intestines release agent - carried to pancreas through circulatory system
isolate agent and purify = secretin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

endocrine system - function and uses

A

group of cells releasing signal into circulatory system at low conc
carried around the body to target
manipulating system/modifying intracellular signalling pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

main regulators for homeostasis

A

endocrine, parasympathetic and sympathetic nervous systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

field in pharmacology

A

regulate blood pressure, cell growth, cancer studies, diabetes or control blood sugar and ion levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

example of pharmacology

A

Renin-angiotensin-aldosterone system

reducing blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

renin-angiotensin-aldosterone system to increase BP

A

decrease in blood pressure = decrease in flow of fluid through tubule to kidney allow cells to absorb
low in sodium due to absorption back into body monitored by glomerulus - juxtaglomerulus system
decrease in BP = decrease in sodium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

renin-angiotensin-aldosterone system - renin

A

cleaves angiotensin = angiotensin 1 - carried in blood to capillaries in kidney and lung
cleaved by enzyme ACE = angiotensin 2 - active hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

renin

A

enzyme released in kidney induced by 2 things acting together in juxtaglomerular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

function of angiotensin

A
affects brain
bind to receptors in kidney
regulate adrenal cortex of adrenal cortex of adrenal gland
cause vasoconstriction of BV
regulate production of ADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

affecting the brain

for angiotensin

A

nerve regulation - sympathetic activity increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

receptor binding - angiotensin

A

in tubule - increase NaCl absorption and excretion of K - not 1:1 - NaCl absorbed more = ionic imbalance - transfer of water with NaCl and absorb water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

regulate adrenal cortex of adrenal gland - angiotensin

A

releases aldosterone

potentiates absorption of NaCl and loss of K

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

regulate production of ADH

A

vasoconstriction and affect collecting ducts part of kidney - allow pores to be put in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

inhibitors - stop activity to decrease BP

A
renin 
ACE
angiotensin 2 receptor
aldosterone 
ADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

renin inhibitor

A

prevent digestion of angiotensinogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

ACE inhibitor

A

prevent cleavage of angiotensin 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

angiotensin 2 receptor inhibitor

A

prevent angiotensin 2 binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

aldosterone inhibitor

A

prevent aldosterone binding to receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ADH inhibitor

A

decrease BP - prevent water absorption and arteriolar vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

receptor in hormonal system

A

highly specific

some have more receptors and some receptors bind to more than one hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

hormonal - low Kd

A

high affinity

hormone released into whole blood system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Kd

A

how strongly they bind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
to have effect in hormonal system
lots of integrated amplification at level of cell with receptor
26
protected transfer system
hormone bound to carrier protein
27
free hormones
bind to receptor - H-CPr must dissociate = H + CPr | hormone action continue for longer and regulate amount of free hormone
28
overall effectiveness depend on
conc of affinity of free hormone no. receptor present on cell efficiency of amplification stop signalling - removed
29
3 main hormone family
Amine-derived peptide lipid and phospholipid
30
Amine-derived hormones
take off COOH from tyrosine and tryptophan decarboxylated = amine e.g. catecholamines and thyroxine
31
peptide hormone
small TRH (3 a.a) and ADH/vasopressin 9a.a protein hormone - insulin and growth hormone glycoprotein hormones - luteinising, TSH - glycosylated
32
lipid and phospholipid hormone
eicosanoids (prostaglandin etc) - in immune system and BV regulation and clotting steroids - derived from cholesterol calcitriol (vit.D) - sterol derived hormone, no metabolic pathway - cant produce from scratch
33
solubility amine-derived and peptide hormones
water soluble - go to receptor will sit at specific phase
34
hormone-receptor interaction
H released from CPr and bind to receptor = hormone receptor complex
35
interaction
``` defined by Kd 1:1 reaction stronger v. specific and Kd reange from 10(-9) to 10(-12) molar reversible ```
36
interaction - 1:1 reaction
[H][R] / [HR]
37
interaction - stronger
more in HR state - smaller ratio | free:bound
38
HR
hormone-receptor
39
interaction - reversible
measure of affinity - ease of separation Kd
40
Kd
[H] | half of all R are bound - [R] = [HR]
41
max biological response
B max most have hormone efficiency far lower than what is seen when all R or bound Kd at 50% level
42
example of max response - insulin
bind on adipocytes = uptake metabolites - occur at max level at 2-3% receptor bound
43
amplification downstream signalling system
[H] need for max response sensitivity of system limiting step in hormonal system - H bind to R - amplification - efficient driven by secondary messenger/ downstream phosphorylation cascade
44
[H] seen by target cell depend on
rate of release rate of delivery rate of degradation and elimination
45
rate of release
depend on synthesis and selection of H | highly regulated of endocrine control by +ve and -ve feedback loop
46
rate of delivery
blood flow to organ(faster) - increase chance of HR complex | carriers - bring H - stop being broken down
47
rate of degradation and eliminating
H-characteristic rate of decay-metabolised and excreted e. g. adrenaline - shutting off secretion H with short half life - decrease rapidly e. g. thyroid hormone - H's long biological half life - effective conc persist
48
ways to measure levels of H
radioimmune assay | elisa
49
radioimmune assay - process
need Ab against H and isolate H radiolabelled = complex and precipitate out radioactive H complex with sample of unlabelled H down with it compare known and unknown conc = amount of H/ molecule - present
50
Ab
antibodies
51
Elisa - needs 2 antibodies - process
plastic surface - capture Ab and H and second Ab bind at another site = amplification system enzyme links to first detected Ab against detecting Ab which build pyramid - enzyme attach = S. oxidised and change colour
52
endocrine system - where receptor are sitting on cell - types
hydrophilic | hydrophobic
53
hydrophilic receptors in endocrine system
ion channel linked | enzyme and G protein linked (need carrier) which have second messenger
54
hydrophobic receptor in endocrine system | plus example
cytoplasmic - no second messenger able to move through membrane and bind to R = turn off effect/ be carried to R to target area e.g. thyroid - gets carried into nucleus - drives mRNA expression
55
where hormones are secreted from - 2 type
primary endocrine organ secondary endocrine organ both secrete H
56
primary endocrine organ example
pancreas, parathyroid H, Pit. etc
57
secondary endocrine organ + example
secrete H as secondary function | e.g. heart, stomach, liver, kidney, small intestine, skin, ovaries and testes etc
58
pheromone
ectohormone - signalling molecules released into environment
59
adipocytes
endocrine hormone | make lectin
60
bone - as endocrine organ have examples
e.g. thymus, muscle etc
61
endocrine(ductless) gland derive from epithelia
adrenal cortex and beta cells
62
endocrine(ductless) gland derive from neurons
neurohormones
63
endocrine(ductless) gland derive from isolated cells
diffuse endocrine cells- intestines | gut, heart etc
64
immune cell - cytokine function
active at low conc and carried in blood
65
controlling endocrine system - simple feedback loop e.g. "A"
``` "A" changes conc gland responds to conc hormone released bind to target cells - respond by releasing/absorbing A repeat ```
66
examples of the simple feed back loop
intestinal H, secretin, Gastrin, CCK insulin, Glucagon-paired
67
beta cells monitor glucose levels - feedback loop
glucagon (alpha cell) - increase blood sugar - breakdown glucagon insulin (beta cell) - decrease blood sugar - absorb glucose
68
regulating extracellular [Ca2+] - 2 hormones used
``` calcitonin - produced by C cells - between follicles in thyroids parathyroid H (pH) by parathyroid - surface of thyroid ```
69
regulating extracellular [Ca2+] process when decrease in [Ca2+]
parathyroid become excited - release pH into blood | pH bind on osteocyte and osteoclast - break down bone
70
regulating extracellular [Ca2+] process (1) in late distal tubule
matrix = Ca2+ - bind on kidney tubule - increase uptake of Ca activated=s kidney - 1,2-DiOH cholecalciferol = decrease Ca secretion and increase its absorption
71
change in [Ca2+] monitored by
C cells - release calcitonin - decrease [Ca2+]
72
hyperparathyroidism - disease
too much primary - more bone breakdown = demineralised calcification and stone formation secondary - renal failure - decrease in Ca2+ by kidney - increase parathyroid activity
73
hypoparathyroidism - disease
too little autoimmune Ab made against parathyroid gland increase action potential in tissue and heart decreases inhibition of voltage gated Ca2+ channel