Pituitary gland and growth hormone

The pituitary gland (PG) is said to be a “master” endocrine gland and through its tropic hormones influences other endocrine glands to secrete hormones that have a variety of effects on body systems. Growth hormone (GH) is a pituitary gland hormone that has direct and indirect effects produced by somatotrophs in early fetal life. It is essential for normal postnatal growth and has diverse effects across multiple physiological systems. The somatotrophic axis is made predominantly of GH, insulin-like growth factor 1 (IGF-1) and other factors regulating growth. This review summarises the relevant anatomical relationships of the PG, the basic aspect of GH physiology which includes mechanism of action (MOA), regulation and secretion and a direct and indirect action of GH through IGF-1, an important mediator of most of the peripheral action of GH.