Lipolysis is a highly regulated process and is controlled by nervous system, hormones, and paracrine/autocrine factors. Dysregulation of lipolysis is associated with some pathophysiological conditions including diabetes, metabolic syndrome, and obesity. Nowadays, special attention isthereforepaid to study lipolysis using different experimental models. This review summarizes the current experimental methods for studying lipolysis. Culture of preadipocyte cell lines, use of differentiated stroma-vascular cells, primary culture of adipocyte, organ culture of adipose tissue, and microdialysis technique are the most widely used techniques to study lipolysis. The advantages and limitations of using these methods are discussed. 1. Introduction Adipose tissue is one of the largest body compartments with various physiological roles including lipid handling and hormone secretion. It is responsible for the storage of fat as triglyceride (via lipogenesis) during times of energy excess and for the mobilization of triglyceride (via lipolysis) during periods of calories deficit . Hormone-sensitive lipase, a rate-limiting enzyme, and monoglyceride lipase catalyse hydrolysis of triglyceride to release fatty acids and glycerol. Unlike fatty acids, glycerol is not reutilized by adipocytes because these cells contain very little glycerol kinase . Therefore, measurement of glycerol gives a good estimate for level of lipolysis . Lipolysis is a highly regulated process and is disciplined by nervous system, hormones (e.g., insulin and catecholamines), and paracrine/autocrine factors (e.g., adenosine, prostaglandins, nitric oxide, and TNF-α) [1, 3–5]. Physical activity, nutrition, gender, age and genetic are also important determinant factors for lipolysis [2, 4]. Dysregulation of lipolysis is associated with a number of pathophysiological conditions such as obesity, diabetes, metabolic syndrome, familial combined hyperlipidaemia, and polycystic ovarian syndrome . Nowadays, special attention is therefore paid to study lipolysis and other aspects of adipose tissue metabolism. While isotopic tracer techniques and arteriovenous difference method allow in vivo estimation of lipolysis, culture of preadipocyte cell lines, primary culture of adipocyte, organ culture of adipose tissue, and microdialysis are of the most used techniques for studying lipolysis in vitro and in situ. This review summarizes the in vitro and in situ techniques for studying lipolysis in animal and humans. Moreover, the advantages and drawbacks of using each method are discussed (Table 1). Table 1:
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