Proceedings of The Physiological Society

University of Liverpool (2002) J Physiol 543P, S188

Communications

The anti-inflammatory effect of leptin on experimental colitis in rats is abolished under stressful conditions

B. Cakir, A. Bozkurt and B.C. Yegen

Marmara University, School of Medicine, Department of Physiology, Haydarpasa, Istanbul, Turkey

Leptin, which is a newly recognised 'anorexic' hormone produced mainly by adipose tissue, regulates food intake and energy balance. Plasma leptin concentrations increase acutely during infection and inflammation (Faggioni et al. 2001), suggesting a modulatory role of leptin in the hypothalamo-pituitary-adrenal (HPA) stress axis as an acute phase reactant (Maruna et al. 2001). It is well known that HPA axis and glucocorticoids have a proliferative activity on the immune system, while stress-induced overactivity of the HPA axis suppresses the immune response. However, it is not clear yet whether leptin has a pro-inflammatory (Barbier et al. 2001) or an anti-inflammatory (Brzozowski et al. 2001) activity in the pathogenesis of intestinal inflammation. Therefore, the present study was designed to investigate the effect of leptin on acute colonic inflammation and this effect was compared with that of acute stress, which is known to act via the HPA axis.

Experimental procedures were approved by the Marmara University Animal Care and Use Committee. After an overnight fast, Sprague-Dawley rats of both sexes (200

Where applicable, experiments conform with Society ethical requirements