Tokyo stocks were slightly lower Friday morning as investors locked in gains after the benchmark Nikkei index’s rise of nearly 3,000 points over an eight-day rally through the previous day. The 225-issue Nikkei Stock Average fell 48.21 points, or 0.17 percent, from Thursday to 28,062.18. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 2.34 points, or 0.12 percent, at 1,979.22. Decliners were led by insurance, pulp and paper, and information and communication issues.