18 Sept 2016

Endocrine system anatomy

Endocrine system is the group of glands that secrete hormones. It regulates tissue function, body metabolism, growth and development, sexual function, reproduction, sleep, and mood.

Endocrine Glands are,

          1.      Hypothalamus

          2.      Pineal gland

          3.      Pituitary gland

          4.      Thyroid gland

          5.      Para thyroid gland

          6.      Adrenal gland

          7.      Pancreas

          8.      Ovaries/ Testes

Endocrine glands secrets their hormones directly into the bloodstream, whereas Exocrine glands produce and secrets substances onto an epithelial surface by way of a duct (Sweat glands, salivary glands, mammary & lacrimal gland)

Hypothalamus is a small portion of the Brain just below the thalamus. It is the neural control centre for all endocrine systems. Hormones are,


            1. Thyrotropin-releasing hormone (TRH)

            2. Dopamine

            3. Growth hormone-releasing hormone

            4. Growth hormone-inhibiting hormone

            5. Gonadotropin-releasing hormone

            6. Corticotropin-releasing hormone

            7. Vasopressin


      Pineal Gland (pineal body): a small gland located at the center of the brain. Produce Melatonin (Regulates sleep) it is also an antioxidant.


     Pituitary Gland is a small gland located at the base of the brain.  Hormones released by the pituitary gland are,


            1. Thyroid-stimulating hormone

            2. Adrenocorticotropic hormone

            3. Gonadotropin (follicle-stimulating hormone & luteinizing hormone)

            4. Growth hormone

            5. Prolactin (Stimulate milk synthesis)

            6. Melanocyte-stimulating hormone (Stimulate melanin synthesis)

            7. Oxytocin (Uterine contraction during delivery)

            8. Vasopressin


     Thyroid Gland is located in the neck just below Adam’s apple. It secretes thyroid hormone (T3 and T4)


       Parathyroid Glands are totally four small glands located in the neck just behind the thyroid gland, it secrets parathyroid hormone that maintain the calcium and phosphate level.


      Pancreas is a part of the digestive organ. it is located in the abdomen cavity behind the stomach. It secrets the most important hormone called Insulin and also the Pancreatic juice that assists digestion and absorption of nutrients in the small intestine.


      Adrenal Glands are located just above the kidneys. It secretes Adrenaline, steroid hormone (aldosterone) and Cortisol


      Testes are the male gonads. The primary function is the production of sperm and to produce testosterone.

      Ovaries are the female gland, the primary function is the production of egg cells (Ovum), It secrets progesterone & estrogen hormone important for the regulation of ovulation and menstruation.


Common Diseases of Endocrine System:

      1.    Diabetes mellitus – High blood sugar level over a prolonged period.


                     A.  Type 1 DM – Pancreas fails to produce enough insulin


                     B.   Type II DM – Cells fails to respond to insulin


                     C.  Gestational DM – Pregnant women develop high blood sugar level


       2.    Hypoglycemia-Low sugar level

       3.    Goiter- Swelling of the neck resulting from enlargement of the thyroid gland

       4.    Hyperthyroidism – Excessive production of thyroid hormone

       5.    Hypothyroidism - Low thyroid hormone

       6.    Osteoporosis- Decreased bone density, increase the risk of fracture.

       7.    Osteomalacia- Softening of the bones caused by impaired bone metabolism

       8.    Gigantism - Excessive growth

       9.    Precocious puberty- Puberty occurring at an unusually early age

      10. Cushing syndrome - A condition that occurs from exposure to high Cortisol levels for a long time.

      11. Addison’s disease - occurs when the adrenal cortex is damaged and the adrenal glands do not produce enough of the steroid hormones Cortisol and aldosterone.

      12. Epididymitis - Inflammation of the tube at the back of the testicle that stores and carries sperm.

      13. Hydrocele - is a collection of fluid in the scrotum.

      14. Polycystic ovary syndrome - Hormonal disorder causing enlarged ovaries with small cysts on the outer edges.

      15. Hyperparathyroidism - is an increased parathyroid hormone (PTH) levels in the blood.


      16. Hypoparathyroidism -  underproduction of parathyroid hormone.



1. BMI - Body mass index

2. DM - Diabetes mellitus

3. DKA - Diabetic ketoacidosis

4. FSH - Follicle-stimulating hormone

5. TSH - Thyroid-stimulating hormone 



Test your knowledge:

            A. Endocrine Anatomy Quiz