The invention relates to a roller bearing of a wheel hub of a motor vehicle comprising a tire pressure control system. Said roller bearing comprises an air guiding channel that extends radially through an external ring and an air guiding channel that extends radially through an internal ring that leads into an intermediate chamber that is arranged between the rows of the bearing bodies and is sealed in relation to said bearing bodies. In order to seal the intermediate chamber in a more simple and effective manner, said intermediate chamber comprises a flow channel that is embodied as a Venturi nozzle.