Is pre-out the same ?

I have an integrated amp with a "pre-out" function . I want to try a
tube amp onto my SS integrated amp through this pre-out connection .
Does this "pre-out" have the same impedance requirements as a
stand alone preamp ? I believe that it is a 1 to 10 ratio of impedance from 
preamp to amp . Or , for instance , a 10k ohm impedance on the preamp out
to 100k ohm impedance for the amp-in . Correct ?

Are there any other requirements that I should consider ?

Thank you and be safe .