Tokyo stocks opened sharply lower on early Thursday morning, with sentiments undermined by overnight falls of U.S. stocks and the yen's appreciation against the dollar. At 9:15 a.m., the 225-issue Nikkei Stock Average was down 187. 17 points, or 1.30 percent, from Wednesday to 14,218.59. The broader Topix index of all First Section issues on the Tokyo Stock Exchange fell 15.08 points, or 1.27 percent, to 1,168. 07. A broad range of shares faced selling, with brokerage, bank and insurance issues leading the way.