| Hg | Symbol for mercury (hydrargyrum). (05 Mar 2000) |
|---|---|
| HG factor | A polypeptide hormone (3485 D) secreted by the cells of the Islets of Langerhans in response to a fall in blood sugar levels. Induces hyperglycaemia. A family of structurally related peptides includes glucagon like peptides 1 & 2 (encoded by the same gene), gastric inhibitory polypeptide, secretin, vasoactive intestinal peptide, growth hormone releasing factor, pituitary adenylate cyclase activating polypeptide, exendins. (18 Nov 1997) |
| HGF | <growth factor> Polypeptide mitogen originally shown to cause cell division in hepatocytes. In the liver, the main sources of hepatocyte growth factor are nonparenchymal cells. It is now clear that hepatocyte growth factor is a mitogen for a number of cell types and it is found in many cells outside the liver, including platelets. Hepatocyte growth factor is synthesised as a single chain precursor that is proteolytically cleaved to give a heavy chain (70 kD) and a light chain (30 kD) linked by a single disulphide bond. It contains multiple copies of the kringle domain. However, both the single chain precursor and the two chain forms of hepatocyte growth factor are biologically active and hepatocyte growth factor is generally isolated as a mixture of the two forms. Hepatocyte growth factor also alters cell motility and is now known to be identical to scatter factor. Acronym: HGF (18 Nov 1997) |
| HGH | <abbreviation> Human growth hormone. See: somatotropin. (05 Mar 2000) |
| HGPRT | <enzyme> An enzyme which plays an important role in the making of ATP and GTP from guanine -- the only way guanine, adenine, or other purine molecules are able to become part of nucleic acids. Biologists study gene action via the incorporation of modified nitrogenous bases into DNA by manipulating the metabolic role which this enzyme plays. Similarly, the enzyme thymidine kinase is used for the same purpose by biologists because it fills the same important and unique role for the pyrimidines (thymine, cytosine, uracil, etc.). Acronym: HGPRT (09 Oct 1997) |