TOKYO, May 8 (Xinhua) -- Tokyo stocks opened essentially flat on Tuesday as investors opted to buy on the back of U.S. shares advancing overnight, while others chose to sell owing to the yen's appreciation against the U.S. dollar, which dents exporters and market sentiment.

As of 9:15 a.m., the 225-issue Nikkei Stock Average shed 12.04 points, or 0.05 percent, from Monday to 22,455.12.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange, meanwhile, added 3.87 points, or 0.22 percent, to 1,777.05.

Early gainers comprised fishery, agriculture and forestry, and metal product issues.

Pulp and paper, and mining issues led those that declined the most in the early minutes after the morning bell.