What Are Hormones And How Does It Function?

What Are Hormones?

Hormones are secreted by cells in endocrine gland as and when necessary. Hormones are messengers and carried in blood to target organs. Hormones maintain normal physiological environment of the human body. Abnormal secretion of hormone can cause under or over anatomical development or physiological function. External supply of hormone is necessary when there is lack of production of hormone in the body. External hormones are supplied a tablet or injection. Hormone therapy often causes unwanted side effects.

The topic covers list of all normal hormones produced in human body and highlights its function.

Physiological Functions of Hormone-

Functions of Hormone-

  • Digestion-
    • Hormone stimulates the target organ such as endocrine gland and cells to produce enzyme.
    • Hormone action causes breaking down of carbohydrate, fat, protein and vitamin to smallest particles, which is absorbed by the intestine.
  • Metabolism-
    • Hormone breaks down the glucose and fat to generate energy needed for daily activities.
  • Growth of Organs-
    • Hormone stimulates normal growth of organs like muscles, bones, uterus, vagina, ovaries, testicles and male sensual organs.
  • Sensual Activities-
    • Male and female sensual and gonadal activities are stimulated by hormone.
  • Reproduction-
    • Hormones create perfect endothelial surface for ovary and sperm for migration.
    • Hormones promote fertilization.
    • Hormones assist in growth of fetus in uterus.
  • Emotions-
    • Anxiety- Hormone controls anxiety.

Endocrine Glands

Endocrine Glands

  1. Pituitary Gland Secretes Following Hormones-

    1. Follicle Stimulating Hormone- Stimulates to secrete estrogen in female and testosterone in male.
    2. Luteinizing Hormone (LH)- Hormone is responsible for gender maturation of male and female.
    3. Prolactin- Stimulates thyroid gland to secrete thyroid hormone and also responsible for maturity of milk producing tissue in females.
    4. Growth Hormone- Stimulates skeletal system and viscera (organs) to achieve normal development as assigned by genetic inheritance.
    5. Thyroid Stimulating Hormone (TSH)
    6. Adrenocorticotropic hormone (ACTH)-
      • Stimulates adrenal gland to secrete corticosteroid and mineralo-corticosteroid hormone.
      • Stimulates testosterone secretion by testicles.
    7. Alpha Melanocyte-Stimulating Hormone (α-MSH)-
      • Vasopressin (Antidiuretics hormone (ADH)- Hormone stimulates kidney tubules to reabsorb water.
    8. Oxycontin– Hormone stimulates uterus to contract during childbirth.
  2. Thyroid Gland-

    Thyroid gland secretes following hormone-

    1. Tri-iodothyronine (T3) and Thyroxine Hormone

      Function of thyroid hormone-

      • Metabolism- Stimulates carbohydrate and fat metabolism
      • Growth- Participates in normal growth of children.
      • Effects on Heart- Improves blood supply by increasing heart rate and dilating blood vessels.
      • Effects on Central Nervous System- Balances between anxiety and sluggish feeling.
      • Maintains Normal Fertility- Low thyroid hormone causes infertility.
    2. Calcitonin- Regulates calcium absorption and distribution.
  3. Pineal Gland-

    Pineal gland lies in brain and secretes following hormone-

    1. Melatonin- Initiates sleep and maintain normal emotional attitude.
    2. Serotonin- Maintain and initiate normal sleep. Prevents anxiety and depression.
  4. Testicular Gland

    Hormone Produced By Testicles-

    • Testosterone-Function of testosterone is as follows-
      • Spermatogenesis- Testosterone and follicular stimulating hormone stimulates testicles to produce sperms.
      • Development of male reproductive organs- testis and prostate
      • Body hair growth, loss and distribution.
      • Muscle and bone development.
  5. Ovary Gland

    Hormones produced by ovary-

    1. Estrogen-
      • Stimulates to achieve maturation of internal and external female organs by puberty.
      • Stimulates uterus for menstruation changes.
    2. Progesterone-
      • Physiological and anatomical changes are triggered by progesterone during pregnancy.
      • Stimulates uterus for menstruation changes with estrogen.
    3. Testosterone
      • Skeletal System- Develops muscle mass and maintains strength in females.
      • Maintains female sensual drive and well being.
  6. Adrenal Glands

    Hormones Produced By Adrenal Glands-

    1. Glucocorticoids(Corticosteroids or Cortisol)-
      • Metabolism- Controls carbohydrate, fat and protein metabolism.
      • Anti-inflammatory- Controls inflammatory changes in the body.
    2. Mineralocorticoids(Aldosterone)-
      • Electrolytes-
        • Maintains normal electrolyte concentration in the body.
        • Controls reabsorption of sodium by renal tubule.
      • Water-
        • Maintain water balance
    3. Androgen
      • Male Characteristics- stimulates development of male characteristics.
      • Responsible for male balding.
      • Sebaceous cyst growth.
      • Stimulates prostate growth.
    4. Catecholamine
      1. Adrenaline
      2. Nor-adrenaline
      3. Dopamine

      Function of catecholamine-

      • Maintain blood pressure.
      • Maintain normal cardiac output (blood flow from heart).
      • Control panic effects.
  7. Pancrease Gland

    Hormone Secreted By Pancreas-

    1. Insulin

      • Metabolism- Regulates carbohydrate and fat metabolism.
      • DNA replication (production)- as and when necessary.
      • Protein Metabolism- Increases protein synthesis and decreases protein breakdown.
      • Treatment of Hyperkalemia– Pushes potassium into cells (cytoplasm).
      • Tissue Blood Flow- Increases tissue blood flow by relaxing arterial smooth muscles.
      • Sodium Excretion- Decreases excretion of sodium by renal tubules.
    2. Glucagon

      • Blood Glucose Level- Glucagon causes increased blood glucose level. The action is opposite that of insulin.
    3. Somatostatin

      • Regulates insulin and glucagon secretion.