Molecular-cellular mechanisms of adrenal

and sex glands hormones action

EPINEPHRINE GLANDS Two parts:

-cortex-medulla

Hormones of medulla - catecholamines

Epinephrine, norepinephrine and DOPA Nature – derivatives of tyrosine Excretion is regulated by sympathetic

nervous system and brain cortex

Functions:Stress hormones. Contraction of vessels,

increase the blood pressure, accelerate pulse. Contraction of uterus muscles. Epinephrine relaxes the muscles of bronchi and intestine.

On carbohydrate metabolism:-activates the decomposition of glycogen in liver

and muscles-activates glycolysis, PPC, TAC and tissue

respirationOn protein metabolism-accelerate the decomposition of proteinsOn lipid metabolism-activates lipase, mobilization of lipids and their

oxidation

Hormones of cortex - corticosteroids

There are more than 50 corticosteroids Nature – steroids Are synthesized from cholesterol

Two groups-glucocorticoids (protein, carbohydrate

and lipid metabolism)-mineralocorticoids (mineral metabolism)

Glucocorticoids

Most important: corticosteron, cortison, hydrocortison

Synthesis is regulated by ACTHAre transported combined with proteinsHalf-life time – till 1 hourIn the decomposition17-ketosteroids

are formed (excretion with urine). Diagnostic significance – index of the function of cortex of epinephrine glands and testis

Functions

• Antiinflammatory, antiallergic, antiimmune

• Adaptive effect• Maintain the blood pressure• Maintain the volume of extracellular

liquid

Effect on protein metabolism

• Stimulate catabolic processes in connective, lymphoid and muscle tissues

• Activate protein synthesis in liver• Stimulate amino transferases• Stimulate the urine biosynthesis

Effect on the carbohydrate metabolism

Increase the glucose level• Activate gluconeogenesis• Inhibit hexokinase (glycolisis)

Effect on the lipid metabolism

• Activate lipolysis• Activate the conversion of FA

into carbs

MineralocorticoidsThe most important hormone:

aldosteronExcretion is controlled by rhenin-

angiothensin systemFunctions:-activate the

reabsorption of Na, water and Cl in kidney canaliculi

- Promotes the excretion of К ions via the kidneys, skin and saliva

Disorders of the function of epinephrine gland

cortexInsufficiency: Addison disease

(bronze disease)Causes: -injury of epinephrine gland cortex-insufficient production of ACTHBlood pressure

decrease, loss of weight, weakness, anorexia.Hyperpigmentation - bronze skin

Hyperproduction: Kushing syndromCauses: hypeplasia or tumor of

epinephrine gland cortexObesity, particularly of the trunk and face (“moon face“) with sparing of the limbs; striae (stretches of the skin)Proximal muscle weaknessHirsutism (facial male-pattern hair growth)Insomnia, impotence, amenorrhoea, infertilityHeart diseases, hypertensionPolyuria, hypokalemia hyperglycemia, glucosuria (steroid diabetes) Kidney bonesDepression, anxietyHyperpigmentation

Aldosterone hyperproductionCauses: -aldosteroma

Symptoms:-hypokaliemia-hypernatriemia-hyperchloremia-hypervolemia-edema,

hypertension

A little amount of female sex hormones is formed in male organism and vice versa.

Female – estrogens, progesteron.

Male – androgens.

Sex hormones

Are synthesized in:-sex glands-placenta-cortex of epinephrine

glands

EstrogensNature: steroidsEstradiol – is formed in follicles of

ovariumEstron and estriol – are formed in liver

and placenta in the metabolism of estradiol

eстрадіол естріол

Functions of estrogensDevelopment of the female reproductive

system organs Ability to fertility in reproductive period

Biochemical functions of estrogens

Anabolic action on the tissues of reproductive organs

Inhibit the exit of Ca from bones (osteoporosis in menopause)

ProgesteronNature: steroidIs formed in corpus luteum, placenta

and epinephrine glands

Functions of progesteronPrepares the endometrium of uterus to

implantation of ovumInhibits the uterus contraction during

pregnancyStimulates the growth of mammary

glands

AndrogensTestosteron

Nature: steroidIs formed in the interstitial cells of

testisIs excreted as 17-кetosteroids

Functions of testosteroneDevelopment of the primary sex

featuresDevelopment of the secondary sex

featuresStimulates spermatogenesis

Biochemical functions of testosterone

Strong anabolic action (stimulates the synthesis of NA, proteins, phospholipids) – increases the mass of muscles

Keeps the Ca and P in organism

Derivatives of androgens – active anabolics

THYROID GLAND

Hormones of two types:

1. Iodine containing : thyroxin (tetraiodthyronin) and triiodthyronin – derivatives of tyrosine;

2. Calcitonin - peptide

Synthesis of iodine containing hormones is regulated by thyrotropic hormone, which in turn is stimulated by thyroliberin

Functions of iodine containing hormones

Necessary for normal growth, differentiation, sex and mental development

Regulate the speed of metabolism

Effect on protein metabolismIn physiological concentration stimulate synthesis of proteins, nucleic acids. In the increased concentration activate the protein decomposition.

Effect on carbohydrate metabolism

Accelerate the absorption of carbohydrates in the intestineActivate the decomposition of glycogen.

Effect on lipid metabolismActivate the exit of lipids from depot, its decomposition and oxidation

Effect on energetic metabolismIn excess thyroxin uncouples respiration and phosphorilation, decreases the ATP formation and increases the heat formation

Hyperfunction of gland – diffuse toxic

goiter (thyrotoxicosis, Graves disease)

•Goiter – hyperplasia of gland•Hypermetabolism•Increase of body temperature•Sweating, muscle weakness•Weight loss with good appetite •Tremor, emotional lability, insomnia •Exophtalm

Hypofunction of gland (occurs in the deficit of iodine in water, soil, air)

•Decrease of metabolism•Decrease of body temperature

Hypofunction in childhood - cretinism•Growth inhibition•Unproportional body development•Disorders of mental development

Hypofunction in adults – mixedema•Edema of mucosa

mixedema

cretinism

Endemic goiter (occurs in the

deficit of iodine in water, soil and

air)

Connective tissue is enlarged in gland and it is increased in size markedly

Calcitonin Is synthesized by

parafollicular cells of thyroid gland

Affects the metabolism of Са and Р - Promotes the transferring of Са2+ from

blood into bones- Inhibits reabsorption of Р in kidneys

(decreases the content of Р in blood due to its excretion with urine)

Increase of calcitonin

- hypocalciemia- hypophosphatemia- hyperphosphaturia

Decrease of calcitonin- hypercalciemia- hyperphosphatemia- hypophosphaturia

PARATHYROID GLANDS Parathyroid hormone - protein

Affects the metabolism of Са and Р

- Promotes moving of Са2+ from bones into blood

- Inhibits reabsorption of Р in kidneys (decreases the content of Р in blood due to its excretion with urine)

- Stimulates the absorption of Ca in the intestine

Дія зв’язана з вітаміном D (утворює активну форму вітаміну D в нирках)

Hyperfunction (Recklinghausen’s disease)

- hypercalciemia- hypophosphatemia- hyperphosphaturia- osteoporosis- Accumulation of Са

in tissues

Hypofunction- hypocalciemia- hyperphosphate

mia- hypophosphaturia- tetanus