SELECT * FROM sys.columns WHERE object_id = OBJECT_ID('dbo.yourTableName')
or
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME ='MyTable'
AND
TABLE_CATALOG='MyDBName'
or
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME ='MyTable'
AND
TABLE_CATALOG='MyDBName'