Improved yield of obese rats using a double coordinate system to locate the ventromedial or paraventricular nucleus

This article describes a highly efficient method for making VMH and PVN-lesioned obese rats by using a newly developed coordinate system. In previous methods, the coordinates for creating VMH and PVN lesions were determined from single point, either the interaural line or the bregma. Because skull size varies, the use of two reference points resulted in greater consistency. We therefore developed a system for making VMH- and PVN-lesioned obese rats using both the interaural line and the bregma. With this new double coordinate system the success rate for producing obese rats varied from 52% to 92% for VMH lesions and from 36% to 61% for PVN lesions.