Leptin (Mouse / Rat) ELISA
The Mouse and Rat Leptin ELISA is a sandwich enzyme immunoassay for measurement of mouse and/or rat leptin.
Leptin is a protein hormone with important effects in metabolism and regulating body weight. It is a single-chain 16 kDa protein consisting of 146 amino acid residues and encoded by the obese (ob) gene.
Leptin is expressed predominantly by adipocytes, small amounts of leptin are also secreted by cells in the epithelium of stomach and in the placenta. Leptin´s effect on body weight is mediated through effects on hypothalamic centers, where leptin receptors are highly expressed. Leptin has a dual action, it decreases the appetite and increases energy consumption. A mutations in the ob gene of leptin or in the gene of leptin receptor causes hyperphagia, reduced energy expenditure, and severe obesity in the ob/ob mice.
Ob gene knockout mice are also characterized by several metabolic abnormalities including hyperglucocorticoidemia, hyperglycaemia, hyperinsulinemia and insulin resistance.
When ob/ob mice are treated with injections of leptin, they lose their excess fat and return to normal body weight.
Studies have shown that leptin appears to be a significant regulator of reproductive function. In addition, leptin is involved in bone metabolism and plays a significant role as an immunomodulator.
In the Mouse and Rat Leptin ELISA, standards, quality controls and samples are incubated in microplate wells pre-coated with anti-mouse leptin antibody. After 60 minutes incubation and washing, biotin labelled polyclonal anti-mouse leptin antibody is added to the wells and incubated with the captured leptin for 60 minutes. After another washing, streptavidin- HRP conjugate is added. After 30 minutes incubation and the last washing step, the remaining conjugate is allowed to react with the substrate solution (TMB). The reaction is stopped by addition of acidic solution and absorbance of the resulting yellow product is measured. The absorbance is proportional to the concentration of leptin. A standard curve is constructed by plotting absorbance values against concentrations of standards, and concentrations of unknown samples are determined using this standard curve.
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