  We present a computational study of the magnetic anisotropy energy for a
given concentration of the Mn ions in the GaAs host, in the framework of the
density functional theory. We focus on the influence of a different kind of
strains on the uniaxial magnetic anisotropy constants $K_1$ and $K_2$, which
reflect the magnetic anisotropy energy out- and in- (001) plane, respectively.
We have shown that the general trends for the applied biaxial strain on
anisotropy constants are consistent with the experimental data. We have
predicted the critical strains, for which the magnetization vector changes its
direction. Our results have shown that it is not possible to modify
considerably the uniaxial magnetic anisotropy constants, exposing (Ga,Mn)As to
hydrostatic pressure of a magnitude reasonable from experimental point of view.
