Sydney, Sept. 6 (BridgeNews) - Moody's Investors Service placed on review for possible downgrade the Aa2 rating of yen-denominated domestic securities issued or guaranteed by the government of Japan. Japan's Aa1 foreign currency country ceilings as well as the government's Aa1 rating for internationally issued bonds (including euroyen) remain unaffected by this action and maintain a stable outlook, the rating agency said.