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Human growth hormone (hGH)

Growth hormone (GH), also referred to as somatotropin, plays an important role in human growth and development. Growth hormone is released from the pituitary. The release is under tight control of a number of hormones and neurotransmitters, either directly or indirectly. It regulates a variety of physiological effects, including linear growth of the animal, lactation, differentiation and electrolyte balance. The molecular mechanism of these biological effects involves the binding of gowth hormone to a specific plasma membrane receptor, referred to as growth hormone receptor (GHR). The growth hormones (GH) from man and from the common domestic animals are proteins of approximately 191 amino acids, synthesized and secreted from the anterior lope of the pituitary. The growth hormone is a key hormone involved in the regulation of not only somatic growth, but also in the regulation of metabolism of proteins, carbohydrates and lipids. Growth hormones from different species share a significant level of sequence homology. Human GH (huGH) is a polypeptide chain of 190 amino acids and a molecular weight of 22 kDa. hGH is one of several hormones secreted by the anterior pituitary gland and, as noted above, influences the growth, regeneration and repair of cells, bones, muscles and organs throughout the body throughout life. Production peaks at adolescence when accelerated growth is occurring and if growing children are deficient in human growth hormone, they remain as pituitary dwarfs. If they have too much they exhibit gigantism (acromegaly). hGH is typically used to treat patients suffering from hypopituitary dwarfism. Human growth hormone directs linear bone growth. Human growth hormone also has lactogenic activity and has been shown to be involved in metabolic processes such as lipid, nitrogen and carbohydrate metabolism. Low hGH levels are associated with the aging process and early onset of disease. Human growth hormone (hGH) participates in much of the regulation of normal human growth and development. This 22,000 dalton pituitary hormone exhibits a multitude of biological effects including linear growth (somatogenesis), lactation, activation of macrophages, insulin-like effects and diabetagenic effects among others. Human growth hormone (hGH) has practically been used for about 20 years as a therapeutic agent for the treatment of pituitary dwarfism and various pharmaceutical formulations are marketed currently.

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