PARTIAL LIPECTOMY, BUT NOT PVN LESIONS, INCREASES FOOD HOARDING BY SIBERIAN HAMSTERS

We tested the inverse relationship between body fat and food hoarding in Siberian hamsters by decreasing or increasing body fat through part ial surgical lipectomy (LIPX) or by making obesity-inducing lesions of the paraventricular nucleus of the hypothalamus (PVNx), respectively. We asked three questions. 1) Is food hoarding increased after body fa t loss due to LIPX? 2) Is food hoarding decreased after PVNx? 3) Does PVNx affect the hoarding response to LIPX? Hamsters housed in a simula ted burrow system increased food hoarding after LIPX followed by a dec rease to pre-LIPX levels as body fat was partially compensated through an increase in the mass of their unoperated fat pads. PVNx hamsters h ad increased body mass and food intake but did not have decreased food hoarding, nor was food hoarding increased by LIPX in PVNx hamsters. T he partial body fat compensation by LIPX + PVNx hamsters suggests that the damaged PVN did not cause a general failure to sense energy defic its but did affect the ability to integrate internal and external ener gy stores.