MOTOR SYSTEMSN-terminal tripeptide of IGF-1 improves functional deficits after 6-OHDA lesion in ratsKrishnamurthi, Rita; Stott, Simon3; Maingay, Matt3; Faull, Richard L. M.1; McCarthy, Dianne2; Gluckman, P.; Guan, J.CAAuthor Information Liggins Institute, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1Department of Anatomy with Radiology 2Department of Psychology, University of Auckland 3NeuronZ Limited, Auckland, New Zealand CACorresponding Author: email@example.com Received 14 March 2004; accepted 17 March 2004 NeuroReport: July 19th, 2004 - Volume 15 - Issue 10 - p 1601-1604 doi: 10.1097/01.wnr.0000127461.15985.07 Buy SDC Metrics Abstract Central administration of N-terminal tripeptide of IGF-1 (GPE) prevents the loss of dopamine neurons. We now examine effects of GPE administered peripherally, on long-term functional recovery after 6-OHDA lesion in rats. GPE treatment (3 mg/kg, i.p.), 3 days after the lesion reduced the number of rotations (p<0.005) and the time over meter (p<0.005) compared to vehicle treatment. Step length and number of adjusting steps were increased in the GPE group (p<0.005), particularly at 12 weeks post lesion. However, GPE treatment did not prevent the loss of tyrosine hydroxylase in the substantia nigra pars compacta and the striatum. The study suggests that peripheral administration of GPE after onset of nigrostriatal dopamine depletion improves long-term Parkinsonian motor deficits, independent of neuronal outcome. © 2004 Lippincott Williams & Wilkins, Inc.