  *AIMS: To study the interaction between young AGN and their host galaxies
based on their ionized gas and radio emission, and to analyze possible
implications for the radio galaxy evolution.
  *METHODS: The [OIII] 5007 line and 5-GHz radio properties are compared and
studied on a large, representative sample of GPS and CSS (i.e., young) quasars
and radio galaxies as well as large-scale sources using [OIII] 5007 line and
5-GHz radio data from literature and our observations.
  *RESULTS: Several correlations between the [OIII] 5007 line and 5-GHz radio
emission have been found. The main result is that the [OIII] 5007 emission is
strongly related to the GPS/CSS source size indicating that the [OIII] 5007
emission is clearly enhanced by the jet expansion through the host galaxy ISM.
Shocks are the most likely enhancing mechanism, although jet-induced star
formation could also be, partly, responsible for the [OIII] 5007 emission. The
data also suggests a possible deceleration of the jet as it grows. In this
case, however, the correlation is weak.
