sentences:  Route U8 also began operating on the particular segment of routes 42 and 44 between Seat Pleasant and Capitol Heights station, during the early 1990s once it was introduced.No changes were made to the 42, 44, 45, 46 Metrobus Routes, which operated as part of the Mount Pleasant Line.Between the 1980s and 1990s, route 45 was discontinued and replace by routes 40, 42, 44, and 46.