Animal models of obesity & their usefulness in molecular approach to obesity.

Obesity, a multifactorial nutrition disorder, is no longer the problem of the affluent West; it has been slowly gaining entry in to developing countries as well. Ever since the first demonstration of an experimental hypothalamic obese rat model, laboratory animals have been in the forefront of basic research concerned with this important metabolic disease. Apart from nongenetic models, an array of genetic murine models of obesity is now available. Over the years the obese loci in these mutants were localised, and most of them have been cloned. Among them leptin and its receptor--the first gene products to be identified, have revolutionised the field, and the possibility of a 'lipostat' mechanism operating in the body is no longer in the realm of imagination. Studies are now on, to identify the murine obese genes in the human population with a view to understand the problem and intervene therapeutically. We have recently developed a new rat model of obesity in our animal facilities, which has several advantages over the existing Western models. It is hoped, that this new model will strengthen and expand our knowledge on obesity--an interesting but complex syndrome.