Hormones. Mechanism of

regulatory effects

prof. Davydov V.V.

Department of biochemistry and molecular biology

Hormones refers to biologically active substances

which are synthesized in endocrine glands, secreted into

the bloodstream and have a regulatory effect on the

metabolism and function of certain visceral organs.

Role of hormones:

- take part in the integration of metabolism in the

various tissues in the human body;

- take part in the adaptation of metabolism to effect of

adverse factors

Classification of hormones

• hypothalamic hormones (liberins, statins);

• anterior pituitary hormones (adrenocorticotropic hormone –

ACTH, growth hormone, follicle stimulating hormone, luteinizing

hormone, luteotropic hormone, thyroid stimulating hormone);

• posterior pituitary hormone (vasopressin, oxytocin);

• thyroid hormones (thyroxine, triiodothyronine, calcitonin);

• parathyroid hormone (PTH);

• pancreatic hormones (insulin, glucagon);

• hormones of adrenal cortex (glucocorticoids, mineralocorticoids)

and adrenal medulla (epinephrine);

• sex hormones (testosterone, estradiol);

Membrane receptor

Cytoplasm receptor

Mechanism regulatory effects of hormones which

bind with intracellular (cytoplasmic) receptors

Mechanism regulatory effects of hormones which

bind with membrane receptors

Classification of hormones which bind with

membrane receptors

№ hormone effector

protein

second

massager

1 ACTH, ТТH,

calcitonin,

glucagon,

epinephrine, FSH,

LH, MSH

adenylate

cyclase

cAMP

2 atrial nairiuretic

peptide

guanylate

cyclase

cGMP

3 Vasopressin (V1),

gastrin, tyroliberin,

gonadoliberin

phospholipase

С

1,2-diacylglycerol,

inositol 1,4,5-

triphosphate, Са2+

4 insulin,

oxytocin

- -

Mechanism of regulatory effect of hormones

which effect are mediated by activation of

adenylate cyclase

Structure of β2–adrenergic receptor

(serpentine receptor)

Mechanism of regulatory effect of hormones

which effect are mediated by activation of

adenylate cyclase

Scheme of G-protein transformations

Mechanism of regulatory effect of hormones

which effect are mediated by activation of

adenylate cyclase

cАMP

N

NN

N

NH2

O

OH

CH2O

O

P

OH

O

Mechanism of activation of protein kinase A by cAMP

Protein phosphorylation by protein kinase A

Enzymes which are regulated by cAMP-dependent

phosphorylation

Enzyme Pathway

Glycogen synthase

Kinase phosphorylase

Pyruvate kinase

Phosphofructokinase

Pyruvate dehydrogenase

complex

Hormone sensitive lipase

Fructose 1,6-bisphospha-

tase

CREB (cAMP response

element-binding protein)

– factor of transcription

Glycogen synthesis

Glycogenolysis

Glycolysis

Glycolysis

Oxidative decarboxylation of

pyruvate

Lipolysis

Gluconeogenesis

CRE of DNA – take part in

the regulation of gene

expression

Mechanism of regulatory effect of hormones

which effect are mediated by activation of

adenylate cyclase

Classification of adrenoreceptors

Effect of cholera toxin

Effect of pertussis toxins

дифтерия

Classification of hormones which interact with

membrane receptors

№ hormone effector

protein

second

massager

1 ACTH, ТТH,

calcitonin, glucagon,

epinephrine, FSH,

LH, MSH

adenylate

cyclase

cAMP

2 atrial nairiuretic

peptide

guanylate

cyclase

cGMP

3 vasopressin,

gastrin, thyroliberin,

gonadoliberin

phospholipase

С

1,2-diacylglycerol,

inositol 1,4,5-

triphosphate, Са2+

4 insulin,

oxytocin

- -

Mechanism formation of the cellular response to

the vasopressin

Reaction, which are catalyzed by phospholipase C

CH2O-CO-R

CHO-CO-R1

CH2

O

POH O

O

OHOH

OH OPO3H

2

OPO3H

2

CH2O-CO-R

CHO-CO-R1

CH2

OH

OPO3H

2

OHOH

OH OPO3H

2

OPO3H

2

H2O+

PL C+

phosphatidyl inositol

4,5-bisphosphate

1,2-diacylglycerol

(DAG) inositol

1,4,5-triphosphate

(IP3)

Mechanism formation of the cellular response to

the vasopressin

Complex calcium-calmodulin

Some intracellular proteins regulated by calcium-

calmodulin complex

Adenylate cyclase

Glutamate decarboxylase

Myosin light chain kinase

Nitric oxide synthase

Ca-ATPase (Ca2+-pump

of membranes)

Mechanism formation of the cellular response to

the vasopressin

Classification of hormones which interact with

membrane receptors

№ hormone effector

protein

second

massager

1 ACTH, ТТH,

calcitonin, glucagon,

epinephrine, FSH,

LH, MSH

adenylate

cyclase

cAMP

2 atrial nairiuretic

peptide

guanylate

cyclase

cGMP

3 vasopressin,

gastrin, thyroliberin,

gonadoliberin

phospholipase

С

1,2-diacylglycerol,

inositol 1,4,5-

triphosphate, Са2+

4 insulin,

oxytocin

- -

Receptor to ANP

Guanylate cyclase reaction

O

N

N

N

N

OH

OH

CH2O

O

P O

OH

NH2

cGMP

GTP + H2O cGMP + H4P2O7

Tyrosine kinase mechanism

effect of hormones

1. Activation of receptor

2.Phosphorylation proteins

3. Activation of MAP kinases

or STAT kinases

4. Activation of genes

expression in nucleus

Thanks for your listening!