Chronic stress induced changes on ingestive behavior in paraventricular nuclues lesioned wistar rats

The paraventricular nucleus of hypothalamus (PVN) is considered as a focal point in regulating stress responses. The idea that the brain categorizes stressors and uses response pathways that vary according to the category has gained significant support in the recent years. The present study was designed to elucidate the possible role of PVN nucleus on stress by evaluating its role in chronic physical & chronic psychological stress on some selective physiological parameters which depicts the ingestive behavior. Wistar albino rats were subjected to chronic swimming (physical) and chronic immobilization (psychological) stress for 60 days with or without bilateral lesions of nucleus of PVN. Food intake, water intake and body weight were measured. Exposure of stressors showed significant alterations in the body weight, food intake and water intake. Stress induced changes observed PVN lesioned rat was significantly more during (P<0.001) during swimming stress than immobilization stress. The data of the present study support the hypothesis that the brain recognizes at least two major categories of stressor, which has been referred to as physical and psychological. Further, our study also provides the supportive evidence that the response of a physical stress to a greater extent is regulated by paraventricular nucleus of the hypothalamus.