Constraint for the Existence of Ellipsoidal Vesicles

Under the spontaneous curvature model of lipid bilayers, the constraints for the existence of equilibrium axisym-metric oblate and prolate ellipsoidal vesicles are obtained from the general shape equation. They degenerate either to the constraint for the existence of a spherical vesicle or to that of a circular cylindrical vesicle given by Ou-Yang and Helfiich Phys. Rev. Lett. 59 (1987) 2486; 60(1988)120; Phys. Rev. A 39 (1989) 5280.