  It is investigated the behaviour of the ``constants'' $G,$ $c$ and $\Lambda $
in the framework of a perfect fluid LRS Bianchi I cosmological model. It has
been taken into account the effects of a $c-$variable into the curvature
tensor. Two exact cosmological solutions are investigated, arriving to the
conclusion that if $q<0$ (deceleration parameter) then $G,$ $c$ are growing
functions on time $t$ while $\Lambda $ is a negative decreasing function on
time.
