We report the results of spectroscopic observations of eight southern polar-ring galaxies (PRGs), in the wavelength range 5900-7300 Angstrom. We find that five out of eight galaxies contain LINERs or Sy nuclei. Taking into consideration all PRGs with available spectral data, we estimate that about half of all PRGs and PRG candidates have either LINER or Seyfert nuclei. The observed widths of the [N II]lambda 6583 line in the nuclei of early-type PRGs follow the linewidth-absolute luminosity relation for normal E/SO galaxies. We found that one of the observed galaxies - ESO 576-G69 - is a new kinematically-confirmed polar-ring galaxy with a spiral host.