  NGC 4945 has an outstanding role among the Seyfert 2 active galatic nuclei
(AGN) because it is one of the few non-blazars which have been detected in the
gamma-rays. Here, we analyse the high energy spectrum using Suzaku, INTEGRAL
and Fermi data. We reconstruct the spectral energy distribution in the soft
X-ray to gamma-ray domain in order to provide a better understanding of the
processes in the AGN. We present two models to fit the high-energy data.
  The first model assumes that the gamma-ray emission originates from one
single non-thermal component, e.g. a shock-induced pion decay caused by the
starburst processes in the host galaxy, or by interaction with cosmic rays. The
second model describes the high-energy spectrum by two independent components:
a thermal inverse Compton process of photons in the non-beamed AGN and a
non-thermal emission of the gamma-rays. These components are represented by an
absorbed cut-off power law for the thermal component in the X-ray energy range
and a simple power law for the non-thermal component in the gamma-rays. For the
thermal process, we obtain a photon index of Gamma=1.6, a cut-off energy of Ec
~ 150 keV and a hydrogen column density of NH = 6e24 1/cm**2. The non-thermal
process has a photon index of Gamma=2.0 and a flux of F(0.1-100 GeV) = 1.4e-11
erg/cm**2/sec. The spectral energy distribution gives a total unabsorbed flux
of F(2 keV - 100 GeV) = 5e-10 erg/cm**2/sec and a luminosity of L(2 keV - 100
GeV) = 9e41 erg/sec at a distance of 3.7 Mpc. It appears more reasonable that
the gamma-ray emission is independent from the AGN and could be caused e.g. by
shock processes in the starburst regions of the host galaxy.
