  We use Gemini GMOS-IFU observations of three luminous nearby Seyfert galaxies
(Mrk79, Mrk348 and Mrk607) to estimate the electron temperature ($T_{\rm e}$)
fluctuations in the inner 0.4-1.1 kpc region of these galaxies. Based on
$T_{\rm e}$ determinations through the [O III]$\lambda5007$/$\lambda4363$
emission line ratio of each spaxel, temperature variations are quantified by
computing the integrated value of the temperature fluctuation parameter
($t^{\rm 2}$) projected in the plane of the sky $t_{\rm A}^{\rm 2}$, for the
first time in Active Galactic Nuclei. We find $t_{\rm A}^{\rm 2}$ values of
0.135, 0.039, and 0.015 for Mrk79, Mrk348, and Mrk607, respectively, which are
of the same order or larger than the maximum values reported in star-forming
regions and planetary nebulae. Taking into account that $t_{\rm A}^{\rm 2}$
should be considered a lower limit of the total $t^2$ in the nebular volume,
the results suggest that the impact of such fluctuations on chemical abundance
determinations can be important in some AGNs.
