Lau, David C. W.Abdel-Hafez, Mohammed S.2005-08-162005-08-1620040612984931http://hdl.handle.net/1880/42203Bibliography: p. 64-80Some pages are in colour.Adipocytes have been shown to release an ever-increasing number of biomediators. However the role of these mediators in adipose tissue development remains unclear. The present study investigated the direct effects of exogenous leptin and other adipose tissue-derived cytokines (TNFoc, IL-I p, IL-6, and TGFP) on preadipocyte differentiation and leptin production in vitro. To determine the role of these agents, rat preadipocytes were induced to differentiate with a hormonal cocktail in the absence or presence of cytokines. Addition of leptin to the hormonal cocktail exerted two significant opposing effects on differentiating preadipocytes, depending on the dose used. TNFa, TGFp and IL-IP exerted significant inhibitory effects on preadipocyte differentiation and leptin production, even in the presence of a stimulatory dose of leptin. IL-6 exerted a significant stimulatory effect on preadipocyte differentiation and leptin production, and enhanced the stimulatory effects of leptin. In summary, the present data suggest that adipose tissue-derived hormones and cytokines may play an important role in regulating adipose tissue development.xii, 80 leaves : ill. ; 30 cm.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.master thesis10.11575/PRISM/15003AC1 .T484 2004 A33