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Home , Adrenal cortex, Adrenal medulla, Zona glomerulosa, Zona reticularis

Adrenal & Gonadal

Topics for today:

• • hormones •Hormone control of organs • hormone synthesis

•Vitamin D3 • and Progesterone

Layers of adrenal cortex

zona fasiculata

1 Hormones of adrenal cortex

zona glomerulosa

zona fasiculata O zona reticularis

HO – dehydroepiandrosterone • increased protein synthesis DHEA is weak with • masculinizing effects in almost no effect in male but has female (hypersecretion) masculinizing effects in females

Adrenal medulla (interior)

• Composed of modified post-synaptic sympathetic neurons • Releases mostly epinephrine. • Has effects similar to those triggered by sympathetic nervous system

Adrenal medulla hormones

HO

HO -CH-CH2 - N-CH3 epinephrine OH H

Effects of epinephrine: • causes elevated blood glucose level • stimulates glycolysis & fatty acid use • increases cardiac output & blood pres • shifts blood flow to skeletal muscle • increases rate and depth of respiration

2 Organ responses to Epinephrine

Causes glycogen Causes fatty acid release degradation in muscle from adipose tissue

fatty glycogen acids trigly- cerides

lactate glycerol

muscle lactate adipose tissue

Causes release of glycogeno lysis glucose from liver glucose ...elevated plasma level liver

Hormone action time

Epinephrine is in group of fast-acting hormones

Fast-acting Hormones Slow-acting Hormones

• • Throxine • Epinephrine • • Insulin • Growth hormone • glucagon • Estrogens • Androgens

Hormone control of (Pathway/metabolic effects)

Insulin Glucagon Epinephrine Cortisol

⇑ Glycogenesis ⇑ Gluconeogenesis ⇑ Glycogen degrad ⇑ Protein degradation ⇑ Glycolysis ⇑ Glycogen degrad ⇑ Glycolysis (effect in muscle) ⇑ Lipid synth (effect in liver) ⇑ Lipid degrad ⇑ Protein synth ⇑ Protein synth ⇑ Gluconeogenesis ⇑ Glycogen degrad (effect in liver)

3 Endocrine disfunctions

CH2OH C=O HO OH Cushing’s syndrome – excessive cortisol resulting in loss of muscle protein O

CH2OH HO C=O Addison’s disease – insufficent O C causing cardiac disturbance due to high K+ O

O Adrenogenital syndrome – excessive androgen causing virilization in female

HO

Steroid synthesis

cholesterol HO

CH2OH C O CH3 progesterone CH3 progesterone O 17-OH progesterone OH desoxycorticosterone O testosterone 19-Nor-testosterone OH cortisol 17-ß-

HO 17-ß-estradiol

Vitamin D3 synthesis

HO cholesterol

OH

CH2

HO 1,25-dihydroxy Vit D3

4 Hormone control of levels

Parathormone Calcitonin .

Renal reabsorption of Ca ⇑ - - Intestinal absorption of Ca - - ⇑ Ca mobilization from bone * ⇑ ⇓ - Serum Ca level ⇑ ⇓ ⇑

* Ca mobilization results from action on hydroxyapatite(the mineral matrix of bone) by acid phosphatase released from osteoclasts.

Ovarian follicles &

Follicular phase - FSH control

follicle cells ( synthesis) primary follicles secondary oocyte mature follicle

LH triggered ovulation

ovum

corpus luteumluteum Luteal phase - LH control

Hormones of the Hormones of the ‘Follicular’ phase:

O O OH OH

HO HO HO estriol 17-ß-estradiol (the “estrogens”)

The ‘Luteal’ phase

CH2OH C O CH3 CH3

O progesterone

5 Hormonal effects of estrogens

General effects: • stimulates bone elongation and then closure of the epiphyseal plates • produce a general ‘anabolic’ effect • stimulates “female” pattern of fat distribution • stimulates mammary gland growth Reproductive system effects:

• stimulates growth of uterus & fallopian tubes • stimulates growth of external genitalia

Synthetic estrogen

OH

HO Diethylstilbestrol (DES) 17-ß-estradiol

Diethylstilbestrol (DES) is a synthetic nonsteroidal estrogen that binds estrogen receptors. It was formerly used to prevent premature labor and also used as a feed additive to promote growth of livestock and poultry. It has been linked to increased risk of vaginal or cervical carcinoma.

Effects of progesterone

• maturation of uterine mucous glands • stimulates uterine glands to secrete mucus • blocks androgen effects (competes for binding)

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