Opiorphin, towards a new drug?
| Author : Pierre Allain
||Date : 2010-10-26
Opiorphin is an endogenous pentapeptide, like sialorphin, which inhibits enkephalinases, neutral endopeptidase and aminopeptidase NR. This inhibition induces a rise in the concentration of some enkephalins whose effects are reinforced. Given by intravenous route to animals, opiorphin has an analgesic effect and an antidepressant effect.
Can opiorphin become a new drug? Opiorphin is a peptide and peptides are hardly absorbed from the digestive tract, cross badly membranes and are rather quickly inactivated in the biological environments, this explains why opiorphin is given parenterally. It is probable that molecules having the properties of opiorphin without being peptides could be found.
The example of the acetorphan, called now racecadotril, which is used only as antidiarrheal, Tiorfan*, shows the difficulty in finding substitutes to morphine.