Evidence for independent osmosensitivity of lateral preoptic and lateral hypothalamic neurons

The purpose of the present study was to determine if a functional or modulatory relationship exists between osmosensitive neurons of the lateral preoptic (LPO) and lateral hypothalamic (LHA) areas. Unit activity was recorded from one neural area (LPO or LHA) following bilateral destruction of the opposite area, i.e., LPO recording site with LHA lesion site, and vice-versa. Bilateral destruction of the LPO or LHA did not eliminate the osmosensitivity characteristics of LPO or LHA units, demonstrating that units of either area do not require input from the opposite area for osmosensitivity.