GnRH analog structural determinants of selectivity for inhibition of cell growth: support for the concept of ligand- induced-selective-signalling

Corresponding author: Prof. R. P. Millar Tel: +44 (0) 131 242 6240 Fax: +44 (0) 131 242 6231 e-mail: r.millar@hrsu.mrc.ac.uk Present addresses: **Centre for Applied Medical Research (CIMA), University of Navarra, Division of Neuroscience, Pamplona-Irunea, 31008, Spain; NIH. ***National Institute on Aging, Johns Hopkins Medical Center, Gerontology Research Center, 5600 Nathan Shock Drive, Baltimore 21224, U.S.A.