  In this article we consider a piston modelled by a potential in the presence
of extra dimensions. We analyze the functional determinant and the Casimir
effect for this configuration. In order to compute the determinant and Casimir
force we employ the zeta function scheme. Essentially, the computation reduces
to the analysis of the zeta function associated with a scalar field living on
an interval $[0,L]$ in a background potential. Although, as a model for a
piston, it seems reasonable to assume a potential having compact support within
$[0,L]$, we provide a formalism that can be applied to any sufficiently smooth
potential.
