Multiple ellipsoid model is applied to the20Ne,34Ne-18Na2,23Na2 and37Na2collision systems. The integral cross-sections for rotational excitation and total collision cross-sections at the incident energy of 190 meV are calculated. Moreover, at the related incident energy, the contributions of different regions of the potential to the integral cross-sections of rotational excitation for20Ne-18Na2,23Na2 and37Na2 collision systems are investigated. By analyzing the differences of these integral cross-sections, the change rules of the integral cross sections with the change of rotational angular quantum number of Na2 molecule, as well as with the change of the reduced mass of symmetric isotopic substituted system are obtained.