ИСТИНА

A common point of view is that stable polar structures are mainly present in/around the early-type galaxies (E/S0) lacking dense gas in their host discs. Indeed, in this case the external matter with an orthogonal orientation of the orbital moment has never experienced any direct collisions with the pre-existing ISM. However, nuclear as well as external polar rings and discs also exist among the late-type hosts, including gas-rich dwarf galaxies. Using the 3D spectroscopic observations of these objects we can derive the rotation properties of the gas components separately in the main and polar planes. The most detailed picture of the gas kinematics and mass distribution properties could be obtained from the combination of optical (HII) and radio (HI) data sets. I briefly review the results of such studies, including the case of direct interaction between the multi-spin gas components.