  We study the behaviour of the non-retarded van der Waals force between a
planar substrate and a single-walled carbon nanotube, assuming that the system
is immersed in a liquid medium which exerts hydrostatic pressure on the tube's
surface, thereby altering its cross-section profile. The shape of the latter is
described as a continual structure characterized by its symmetry index $n$. Two
principle mutual positions of the tube with respect to the substrate are
studied: when one keeps constant the minimal separation between the surfaces of
the interacting objects; when the distance from the tube's axis to the
substrates bounding surface is fixed. Within these conditions, using the
technique of the surface integration approach, we derive an integral form of
the expressions which give the dependence of the commented force on the applied
pressure.
