  The paper is devoted to an algebraic interpretation of Kuznetsov's theorem
which establishes the assertoric equipollence of intuitionistic and
proof-intuitionistic propositional calculi. Given a Heyting algebra, we define
an enrichable Heyting algebra, in which the former algebra is embedded.
Moreover, we show that both algebras generate one and the same variety of
Heyting algebras. This algebraic result is equivalent to the Kuznetsov theorem.
The proposed construction of the enrichable `counterpart' of a given Heyting
algebra allows one to observe that some properties of the original algebra are
preserved by this embedding in the counterpart algebra.
