Male cats can continue to spray urine after neutering. The chances do decline, however, due to the fact that male cats often spray to let females in the area know that they are available to reproduce. Once the cats are neutered, the need for this type of marking often diminishes.
The main reason male cats spray urine is to leave messages for other cats. The messages they send let other cats know that the sprayed area is their territory, how long ago they were there or when they may return. Male cats living in multiple-cat households are more likely to mark areas with urine than their solitary counterparts.