[translations] Text between braces {}

Hi, How should the text between braces {} be translated? For example, in general.pot file in drupal-pot-6.x-1.0-rc1.tar there is this string: Primary Key: The {node}.vid of the node. Should I leave "{node}.vid" as it is? Or should I translate it? How does it appear in the first place? Will "{node}.vid" be replaced with something else? Thanks, Khaldoon Sinjab