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1

What does hormone mean in greek

Classical and modern definition of hormones

I excite, I arouse

Chemical messenger released by one type of cells and carried in the bloodstream to act on specific target cellls. Includes factors produced and used locally without entering the blood stream

2

Who is father of endocrinology

Ernest Starling

3

Why communication between cells is required

-development from the fertilzed egg to the adult organism (differentiation)

-Maintenance of the environment in which cells can live (homeostasis)

-Reproduction

In multicellular organisms cells have to communicate

4

3 layers of signaling networks

Within the cells (intracellular)

Between groups of cells (tissues) intercellular

Between tissues (intertissual)

 

5

What process opposes networks change?

Homeostasis 

6

How old is the earth

when life evolved

when multicellular organisms evovled

earth-4.5 billion years

life-3.8 billion years

Multicellular- 600 million 

7

Main control systems of the body

Nerbous system (direct connection between organs concerned)

Endocrine system (sending chemcial messages hoemones into circulation)

8

Different types of cells producing signals

Neuroendocrine- epinephrine form medulla

9

In what concentrations hormones are usually present and they can be made of

-Very low in concentration
-(ng/ml) or (pg/ml)

 

-Can be peptides (3 to > 180 aa), modified aa,
cholesterol based (steroids), synthesized from fatty
acids (prostaglandins) or gases (nitric oxide)

10

How many receptors each hormone has

only 1

11

decribe general pathway of cellular repsonse to a hormone for membrane bound receptor

-Recognition of
signal by receptor
-Change of
intracellular
network of proteins
-Activation of
target genes or
proteins
-Cellular response

12

What chemical nature anad their subclasses hormones can be

1) Lipids
-Steroids
-Eicosanoids
2) Proteins
-Short polypeptides
-Large proteins:
Chemical modification through glycosylation
3) Amino acid derivatives

13

What response a hormone can induce in general

Metabolic enzyme (activation/inactivation)->altered metabolism

Gene regulatory protein->altered gene expression

Cytoskeletal protein->altered cell shape or movement 

14

What usual signals cell receive and when it willundergo programmed death

Basic ABC signals are always there

15

Derivatives of cholesterol: what structure they have, what properties, source and where found in cell

– Large molecule
• Hydrocarbon ring

oh group

hydrocarbon tail
– Highly hydrophobic
– Source
• Diet
• De Novo synthesis
– Found in cell membrane

16

derivatives of cholesterol and what characteristic they share

– Vitamin D
– Bile acid
• Lipid digestion
– Steroid hormones
• Sex steroids
• Adrenal steroids
– All cholesterol
derivatives contain
sterol ring
 

17

Do male and female sex hormones look alike?

Testosterone and estradiol have chemically very similar formula

The difference is in functional group and methyl group

But structurally 2 hormones are vey different

18

Steroid hormones classes and subclasses and what do they do

-Adrenal
• Mineralocorticoids
– Affect mineral homeostasis
• Glucocorticoids
– Affect glucose metabolism and
immune function
-Gonads (testis and ovaries)
• Estrogens
• Progestogens
• Androgens

19

Lipid hormones are metabolites of what acid

20 c fatty acid (arachidonic acid)

20

what chemicals can be produced from arachidonic acid and function

-Prostaglandins
– Produced by numerous
tissues and organs
• Originally isolated from
prostate gland secretion
• Inflammatory reaction
• Reproduction

21

Prostaglandinds and related compounds are collectively known as 

Eicosanoids

22

IUPAC name for arachidonic acid

5,8,11,14-eicosatetraenoic acid

23

Example of SCAAs that serve as neurohormones

GnRH(10)

Oxytocin(9)

TRH(3)

24

Difference in structure and function of arginine vasopressin and oxytocin

vasopressin has 3-Phe and 8-Arg

Oxytocin 3-Ile, 8-Leu

Arginine vasopressin: Vasoconstriction/Water retention
Oxytocin: Milk ejection/Labor

25

Subunits in large hormones are linked by

Disulfide bridges insulin, growth hormone)

26

tyrosine metabolites

Thyroxine (T4)

Triiodothyronine (t3)

27

Adrenal  medulla produces what AAs metabolites

Epinephrine

Norepinephrine

Dopamine

28

How cells producing hormones can be localized

Cells that synthesize hormones may be clustered in endocrine gland or be interspersed as single cells in organs

29

Endocrine gands composition

Parenchyma (mass of cells)
• Secretory cells
– Blood vessels
• Highly vascularized
– No ducts

30

Permanent or transsitient endocrine glands

Pituitary, adrenal, pancreas
– Ovarian follicle and corpus
luteum