2. ADRENAL SEX HORMONES
• These are secreted by;
a) Zona reticularis (mainly).
b) Zona fasciculata (less quantities)
• Most of the hormones are male sex hormones
(androgens).
• Estrogens and progestrones are also secreted
by adrenal cortex (small quantity).
3. • Androgens secreted by ad.cortex are;
1. Dehydroepiandrosterone.
2. Androstenedione.
3. Testosterone.
• Dehydroepiandrosterone is the most active
adrenal androgen.
• The androgens in general are responsible for
masculine features of the body.
4. • In normal conditions, the adrenal androgens
have insignificant physiological effects
because of low secretion (low amount) both in
males and females.
• In congenital hyperplasia of ad.cortex or
tumor of zona- reticularis, an excess amount
(quality) of androgens is secreted.
• In males, it does not produce any special
effects because large quantity of androgens
are produces by testes also.
5. • In females, the androgens produce masculine
features.
• Some of the androgens are converted into
testosterone.
• Testosterone is responsible for the androgenic
activity in androgenital synd. or congenital ad.
hyperplasia.
6. ADRENOGENITAL SYNDROME
• Under normal conditions, adrenal cortex
secretes small quantities of androgens which
do not have any significant effect on sex
organs or sexual function.
• However, secretion of abnormal quantities of
adrenal androgens develops adrenogenital
syndrome.
• Some of the androgens are converted into
testosterone.
• Testosterone is responsible for the androgenic
activity in adrenogenital syndrome.
7. CAUSE:
• It is due to the tumor of zona reticularis in
adrenal cortex.
Symptoms:
• Adrenogenital syndrome is characterized by
the tendency for the development of
secondary sexual character of opposite sex.
8. • Symptoms in females:
Increased secretion of androgens causes
development of male secondary sexual
characters. The conditions is called adrenal
virilism. The symptoms are:
i. Masculinization due to increased muscular
growth.
ii. Deepening of voice.
iii. Amenorrhea
iv. Enlargement of clitoris
v. Male type of hair growth.
9. • Symptoms in males:
Sometimes, the tumor of estrogen secreting
cells produces more than normal quantity of
estrogens in males. It produces some symptoms
such as:
i. Feminization
ii. Gynecomastia (enlargement of breast)
iii. Atrophy of testis
iv. Loss of interest in women.
10. CONGENITAL ADRENAL HYPERPLASIA
• It is a congenital disorder characterized by
increase in size of adrenal cortex.
• Size increases due to abnormal increase in the
number of steroid secreting cortical cells.
Causes:
• Even though the size of the gland increases,
cortisol secretion decreases.
• It is because of the congenital deficiency of
the enzymes necessary for the synthesis of
cortisol, particularly, 21 –hydroxylase.
11. • Lack of this enzyme reduces the synthesis of
cortisol.
• It in turn, increases the secretion of ACTH from
pituitary by feedback mechanism.
• ACTH stimulates the adrenal cortex causing
hyperplasia with the accumulation of lipid
droplets.
• Hence, it is also called congenital lipid adrenal
hyperplasia.
• Cortisol cannot be synthesized because of lack of
21 –hydroxylase.
• Therefore, due to the constant simulation of
adrenal cortex by ACTH, the secretion of
androgens increases.
• It results in sexual abnormalities such as virilism.
12.
13. Symptoms:
• The characteristic features of adrenal
hyperplasia are virilism and excess body
growth.
• In boys: adrenal hyperplasia produces a
condition known as macrogenitosomia
praecox.
• The features of this condition are:
i. Precocious body growth, causing stocky
appearance called Infant Hercules.
ii. Precocious sexual development with
enlarged penis even at age of 4 years.
14. • In girls: in girls, adrenal hyperplasia produces
masculinization.
• It is otherwise called virilism.
• In some cases of genetic disorders, the female
child is born with external genitalia of male
type. This condition is called pseudo -
hermaphroditism.
15. HYPERALDOSTERONISM
• Increased secretion of aldosterone is called
hyperaldosteronism.
Causes:
• Depending upon the causes,
hyperaldosteronism is classified in to two
types:
i. Primary hyperaldosteronism.
ii. Secondary hyperaldosteronism.
16. i. Primary hyperaldosteronism.
• It is otherwise known as Conn's syndrome.
• it develops due to tumor in zona glomerulosa
of adrenal cortex.
ii. Secondary hyperaldosteronism.
• It occurs due to extra adrenal causes such as:
1. Congestive cardiac failure
2. Nephrosis
3. Toxemia of pregnancy
4. Cirrhosis of liver.
17. Signs and symptoms:
i. Increase in ECF volume and blood volume.
ii. Hypertension due to increase in ECF volume and
blood volume.
iii. Severe depletion of potassium. Prolonged
depletion of potassium causes renal damage.
The kidneys fail to produce concentrated urine.
It leads to polyuria and polydipsia.
iv. Muscular weakness due to potassium depletion.
v. Metabolic alkalosis due to secretion of large
amount of hydrogen ions into renal tubules.
Metabolic alkalosis reduces blood calcium level
causing tetany.
18. • Escape phenomenon:
In primary hyperaldosteronism. Edema does not
occur in spite of increased ECF volume. It is due
to escape phenomenon, which involves pressure
diuresis and ANP.