LOS ANGELES, Jan 17 (Reuters) - Shares of British neuroscience drug developer Amarin Corp. Plc (AMRN.O: Quote, Profile, Research) rose nearly 52 percent on Tuesday as encouraging preclinical data extended a run-up that began in December with a private equity placement. The stock gained $1.01 to close at $2.96 on Nasdaq, nearly triple the $1.01 per share purchase price of the $26.4 million private placement announced on Dec. 22, 2005.