  I explore a possibility to measure the gravitational redshift (GR) effect in
the gravitational field of massive central nuclei residing in active galaxies
(AGN). The activity of central nuclei is associated with the bipolar jet
ejection of relativistic plasma which produces strong radio emission. I
consider the behavior of the flux density variations of the jet plasma as a
result of GR effect from a Schwarzschild black hole, and I discuss
possibilities to detect the GR effect from the relativistic jets of compact AGN
with present and future radio facilities.
