Used in biomedical research to measure cortisol levels in rat biological samples such as serum, plasma, or tissue homogenates. This ELISA kit enables researchers to study stress responses, adrenal function, and the hypothalamic-pituitary-adrenal (HPA) axis activity in laboratory animals. It is widely applied in pharmacology, endocrinology, and neuroscience studies where accurate quantification of cortisol is essential for assessing physiological and pathological conditions related to stress, metabolism, and immune regulation. The assay provides high sensitivity and specificity, allowing for reliable detection of cortisol concentration changes in experimental models.