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The following points highlight the functions of various types of cortical hormones. The Functions are: 1. Mineralocorticoids 2. Functions of Glucocorticoids 3. Functions of Adrenal Sex Steroids.

Cortical Hormones # Mineralocorticoids:

This hormone is mainly secreted from zona glomerulosa.

Principal functions are given below:

1. On Mineral Metabolism:

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(a) Mineralocorticoids help to increase the rate of tubular reabsorption of so­dium (Na+) from the renal tubules.

(b) It increases the excretion of K+ from distal convoluted tubule and collect­ing tubule to maintain the K+ concen­tration.

(c) Helps in retention of NaCI.

(d) Increased secretion may cause alka­losis while decreased secretion pro­motes acidosis.

2. On Water Metabolism:

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Helps in absorp­tion of water from renal tubules to main­tain the water balance.

3. On Blood Protein:

Helps in increase of haemoglobin and plasma protein.

4. On Fat:

Stimulates fatty acid synthesis.

5. On Cardiovascular System:

(a) Hyper-secretion increases the car­diac output, while hypo-secretion re­duces the cardiac output.

(b) Excess secretion increases the arte­rial blood pressure.

6. On Fluid Volume:

(a) This hormone stimulates the thirst centre and as a result person shows thirsty.

(b) Helps to increase the plasma volume.

7. On Cellular Mechanism:

Helps in diffu­sion of lipid in cellular membranes of tu­bular epithelial cells.

Cortical Hormones # Functions of Glucocorticoids:

Glucocorticoids are primarily secreted from zona fasciculata.

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Glucocorticoids possess the following functions:

1. On Carbohydrate Metabolism:

(a) Promotes gluconeogenesis in liver specially from proteins to increase blood glucose level.

(b) Stimulates glycogenesis in liver and muscle.

(c) Helps in phosphorylation of glucose- 6-P.

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(d) Helps in absorption of glucose from intestine and renal tubule.

2. On Protein Metabolism:

(a) It stimulates protein synthesis in liver, but reduces protein synthesis in muscle.

(b) Glucocorticoids accelerate the breakdown of protein and inhibit amino acid uptake in extra-hepatic cells.

(c) It depresses amino acids transport into muscle cells.

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(d) It enhances transport of amino acids in hepatic cells.

(e) It promotes urea synthesis in liver in presence of arginase and argino suc­cinate synthetase.

3. On Fat Metabolism:

(a) Glucocorticoids increase lipolysis in adipose tissue and may raise free fatty acids in plasma.

(b) It stimulates the synthesis of triglyc­erides in the liver.

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(c) Helps in metabolism of fatty acids to ketone bodies.

(d) Stimulates fat absorption from the in­testine.

(e) It stimulates the mobilization of fatty acids and glycerol from adipose tis­sue in the blood.

4. On GI System:

(a) It stimulates oxyntic cells of stomach for secretion of HCI.

(b) It stimulates secretion of trypsinogen and pepsinogen.

(c) It inhibits absorption of calcium from small intestine.

5. On Nervous System:

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(a) It influences the survival neurons.

(b) Maintains the structural integrity of brain.

(c) Excess secretion leads to reduction in threshold of electrical stimulation of brain which may cause convul­sion.

6. On Ca++ metabolism:

(a) It reduces intestinal Ca++ absorption.

(b) It increases urinary Ca++ excretion.

7. On Respiratory System:

It causes matu­ration of foetal lung.

8. Effects on Cardiovascular System:

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(a) It stimulates cardiac output.

(b) It increases blood pressure by en­hancing the action of catecholamine’s.

(c) It reduces capillary permeability.

9. On Muscular System:

It causes loss of muscle power.

10. On Inflammatory and Immunologic Ef­fects:

(a) It inhibits inflammatory and allergic reactions.

(b) Decreases the number of circulating monocytes, eosinophil’s and lympho­cytes.

(c) Reduces the migration of leucocytes into affected tissue.

(d) Prevents histamine release from mast cells.

(e) Inhibits the synthesis of IL-1.

11. On RBCs:

It increases red blood cells count.

Cortical Hormones # Functions of Adrenal Sex Steroids:

Zona reticularis secretes adrenal sex ste­roids. 

Principal functions of sex steroids are given below:

1. Effects in Males:

(a) May influence the growth and differ­entiation of secondary sex organs and features including pubic and axillary hair.

(b) The adult individual can cause op­posite sex attraction, coarsening of the voice.

(c) Helps is growth of muscular, growth of sex glands and increases BMR.

2. Effects in Females:

(a) These hormones may be responsible for libido in women.

(b) Overproduction may cause hirsutism and virilization.

(c) Hyper-secretion may cause involu­tion of female secondary sex char­acters.

(d) May cause development of mam­mary gland, more subcutaneous fat, less body hair and feminine voice.