Vol.33, núm.1, Gac Med Bol, Mayo 2010, pp. 63-68. ISSN 1012-2966.

Obesity and leptin resistance

[Review in Spanish]

¹. Martha Morales Clavijo, ². Carola F. Carvajal Garcés

Abstract

Obesity appears as a result of the balance between the individual's calorie consumption and energy expenditure. The are numerous neuroendocrinal factors responsible for regulating the energy metabolism; however, it was the discovery of the leptin that opened the way for numerous investigations destined to lay bare the mechanisms involved in this homeostasis. The leptin is a peptide of 167 amino acids, with a signal sequence of 21 amino acids that split up before the leptin enters the circulatory torrent. The with adipose tissue is the main producer of leptin, acting as a "marker" of the body's energy reserves. Leptin intervenes in different physiological processes such as the regulation of the energy balance, the control of appetite and body weight, the metabolism of fats and glucides or reproduction, amongs others. There are numerous ob receptors on the central nervous system and in different regions of the hypothalamus that are involved in part of the observed effects of this hormone. Besides, there are ob receptors in numerous peripheral tissues such as the lung, kidney, liver, skeletal muscle, adipose tissue, testicules. The study of this regulation, connections and effects on the central nervous system are proving to be essential for an understanding of the system of regulation of the energy balance and the mechanism involved in the development of obesity.

KEY WORDS: Leptin. Obesity. Energy balance. Ob receptors. Central nervous sistem.