Somatotrophin releasing hormone. Polarised light micrograph (PLM) of the crystalline structure of somatotrophin releasing hormone. This hormone, also known as growth hormone releasing hormone (GHRH), controls body growth by means of its effect on a second hormone, growth hormone. It is produced in the hypothalamus and promotes the release of growth hormone from cells in the anterior pituitary gland. Secreted growth hormone stimulates cell division and protein synthesis in tissues such as bone and cartilage. Magnification: x100 at 4x5 inch size.