Pubdate: Thu, 03 May 2001 Source: Irish Examiner (Ireland) Copyright: Examiner Publications Ltd, 2001 Contact: http://www.examiner.ie/ Details: http://www.mapinc.org/media/144 Author: John von Radowitz DRUG ADDICTION LINKED TO PROTEIN A GROWTH promoting protein in the brain may be partly responsible for Parkinson's disease, drug addiction and schizophrenia, scientists said yesterday. The protein, Brain Derived Neurotrophic Factor (BDNF) was thought to be needed simply for the proliferation, maturation and survival of nerve cells. But a team of French researchers has found it also boosts levels of a receptor molecule called D3 which allows neurones to respond to dopamine. Dopamine is a key chemical which enables neurones to communicate with one another. Faults in the dopamine message system are believed to be involved in brain disorders, including Parkinson's and schizophrenia, as well as drug addiction. The scientists, led by Olivier Guillin from the Unite de Neurobiologie et Pharmacologie Moleculaire in Paris, conducted experiments with rats genetically engineered to provide a "model" of Parkinson's disease. They found evidence that a reduction in BDNF levels leads to fewer D3 receptors. Further studies revealed BDNF is needed for the normal increase in D3 production that occurs shortly after birth. They also discovered BDNF in rats affects their response to levodopa, a compound from which neurones produce dopamine. - --- MAP posted-by: GD