Tokyo shares ended the morning session lower on Monday on a downgraded Japan's GDP data, as well as a sentiment of cashing in on recent gains after Nikkei's four- day uptrend. The 225-issue Nikkei Stock Average lost 152.74 points, or 1.0 percent, from Friday to 15,121.33. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 10.59 points, or 0.86 percent, at 1, 226.38. Decliners were led by real estate, paper and pulp, and nonferrous metal issues.