Study of the glands and hormone of the body is called Endocrinology. Father of endocrinology - T. Addison. Glands are two types - Ducted glands and Ductless glands. Ducted glands produce their secretions through articular ducts. Lachrymal glands, salivary glands, liver and sweat glands are ducted glands. Endocrine glands are ductless glands. Ductless glands leave the secretions directly into the blood stream. 'Non-nutrient chemical messengers' of the body is known as Hormones. The term 'hormone' was first coined by E. H. Starling in 1905. First discovered hormone is known as Secretin.


  Adams Apple               -     Thyroid gland

  Master gland               -      Pituitary gland

  Growth gland              -      Pituitary gland

  Biological clock           -      Pineal gland

  Growth hormone        -     Somatotropin

  Emergency hormone  -    Adrenaline

  Hormones of flight      -    Adrenaline

  Surgical hormone        -    Noradrenaline

  Juvenile hormone        -    Thymosine

  Youth hormone             -    Thymosine


  The one heterocrine gland ( which act as both endocrine and exocrine gland ) in the human body is Pancreas. Organized endocrine bodies in our body is Pituitary, pineal, thyroid, adrenal, pancreas, parathyroid, thymus and gonads.

Other Hormones,

  Stomach          -       Gastrin, Somatotropin

  Duodenum      -       Secretin , Cholecystokinin

  Liver                 -       Angiotensinogen, Angiotensin

  Kidney              -      Renin, Erythropoietin

  Placenta           -      Progesterone, HCG, HPL

  Uterus               -     Prolactin, Relaxin

  Heat                  -     Atrial natriuretic peptide

  Brain                 -     Natriuretic peptide

  Bone marrow  -     Thrombopoietin

  

PITUITARY GLAND

   

     Pituitary gland is known as Master gland. Hormones produced by the anterior lobe of pituitary gland - Growth hormone (GH), Prolactin (PRL), Thyroid stimulating hormone (TSH), Adrenocorticotrophic hormone (ACTH), Luteinizing hormone (LH), and follicle stimulating hormone (FSH). Overproduction of somatotropin caused Gigantism. Under production of somatotropin is caused Dwarfism. Gland which controls all other endocrine glands - Pituitary gland. Milk secreting hormone produced by pituitary gland - Prolactin.

Location of Glands

• Pituitary gland is located at the base of the brain near to the hypothalamus.

• Thyroid gland is a bilobed gland in the neck located just below the larynx.

• Adrenal glands are situated over the kidneys which controls blood pressure.

• The pineal gland is located on the dorsal side of the forebrain.


PINEAL GLAND

   

     Melatonin and Serotonin are the hormones secreted by pineal gland. Melatonin plays an important role in the regulation of 24 hour rhythm ( circadian rhythm ) of our body.

• Melatonin is a derivative of amino acids - Tryptophan

Pineal gland is also known as 'Biological clock' in human body. Melatonin hormone is nicknamed as hormone of darkness (Melatonin is produced in pineal gland when it is dark outside). Melatonin is also functions as an Antioxidant. Melatonin is also known as 'Sleep hormone'. Deficiency of melatonin causes Sleeplessness. 
Serotonin is known as Neurotransmitter. Serotonin has an important role in sending messages between nerve cells. Reduced sunlight can cause a drop in serotonin. A drop in serotonin affects mood ( causes depression).

THYROID GLAND

   
     Thyroid gland is the largest endocrine gland in human body. Thyroid gland secretes the hormones are Thyroxine and Calcitonin. Thyrocalcitonin is the protein hormone secreted by thyroid gland. Under secretion of thyroxine causes Hypothyroidism. Over secretion of thyroxine causes Hyperthyroidism. Persistent hyperthyroidism may lead to Graves disease. The disease which is known as graves disease - Exophthalmic goitre. Thyroxine contains rich quantity of Iodine which is essential for metabolism. Iodine is the mineral required for the healthy functioning of thyroid gland. Thyroid gland controls growth and metabolism. Enlargement of thyroid gland due to the insufficient iodine in the diet is called Simple goitre.

Normal level of calcium in blood - 
           10 - 12 mg/100ml

• Hormone which lowers the concentration of calcium in blood when it rises above normal value - Calcitonin
• Which hormone increases the rate of almost all chemical reaction in all cells of the body - Thyroxine

PARATHYROID GLAND


     Parathyroid gland is situated behind thyroid gland. Parathormone is produced by parathyroid gland. Parathormone hormone raises the concentration of calcium in blood when it lowers below the normal level.

THYMUS GLAND


     Thymus gland is also known as Juvenile gland. Thymus gland is located behind the sternum. Hormone secreted by thymus gland is called Thymosin. Thymosin hormone plays a major role in the differentiation of Tv- lymphocytes which provide immunity to human body. Thymosin hormone is known as Juvenile hormone. Thymus gland is fully developed at the age of 7 and degenerates and disappears after the age of 14, because of the activities of the sex glands.