  Nuclear regions of galaxies generally host a mixture of components with
different exitation, composition, and kinematics. Derivation of emission line
ratios and kinematics could then be misleading, if due correction is not made
for the limited spatial and spectral resolutions of the observations.The aim of
this paper is to demonstrate, with application to a long slit spectrum of the
Seyfert 2 galaxy NGC 1358, how line intensities and velocities, together with
modelling and knowledge of the point spread function, may be used to resolve
the differing structures. In the situation outlined above, the observed
kinematics differs for different spectral lines. From the observed intensity
and velocity distributions of a number of spectral lines and with some
reasonable assumptions to diminish the number of free parameters, the true line
ratios and velocity structures may be deduced. A preliminary solution for the
nuclear structure of NGC 1358 is obtained, involving a nuclear point source and
an emerging outflow of high exitation, as well as a nuclear emission line disk
rotating in the potential of a stellar bulge and expressing a radial excitation
gradient. The method results in a likely scenario for the nuclear structure of
the Seyfert 2 galaxy NGC 1358. For definitive results an extrapolation of the
method to two dimensions combined with the use of integral field spectroscopy
will generally be necessary.
