The asymptotic behaviour of the π0 γ∗ γ∗ vertex

The Bjorken-Johnson-Low theorem applied to the γ∗ → γ∗ π0 process provides us with a rather remarkable asymptotic behaviour for the π0 γ∗ γ∗ vertex. We compare our result with previous QCD- inspired estimates and argue that the redicted behaviour is quite consistent with the present data on hadronic JΨ decays and ensures the matching of long- and short-distance radiative corrections to π+ → e+ νe.