The aim of this study was to validate two commercially available ELISA assays for total ghrelin measurement in dogs: one canine-specific and one originally designed for measuring human ghrelin. The two assays showed intra-assay coefficient of variations (CVs) lower than 10%, while the inter-assay CVs exceeded the 15% limit. Sample dilutions resulted in linear regression equations with correlation coefficients close to 1.
To compare methods and verify ability of the ghrelin assays to differentiate between low and high levels, ghrelin concentrations were measured in plasma samples obtained before and at different times after glucose administration in five Beagle dogs. A statistically significant change in ghrelin after glucose administration was recorded only with assay B.
The human ELISA validated in this study showed a good intra-assay precision, accuracy and, when applied to the glucose injection study, was better at distinguishing high and low canine ghrelin levels than the canine ELISA assay.
Source : A. Tvarijonaviciute et al., 2010. Validation of two ELISA assays for total ghrelin measurement in dogs. JAPAN online December 2010. doi: 10.1111/j.1439-0396.2010.01112.x