how-to find the table name with the primary key by a given foreign key in SqlServer 2005 / 2008

SELECT TC.TABLE_NAME as tableName 
                        FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU
                        JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS TC
                        ON KCU.CONSTRAINT_NAME=TC.CONSTRAINT_NAME 
                        WHERE column_name='Region_Code'
                        AND CONSTRAINT_TYPE='PRIMARY KEY'

                        AND KCU.ORDINAL_POSITION=1