We report the development of a method to analyze receptor and β-arrestin2 mobilization between Class A and B GPCRs via time-resolved fluorescent microscopy coupled with semiautomated high-content multiparametric analysis. Using transiently expressed, tagged β2-adrenergic receptor (β2-AR) or parathyroid hormone receptor type 1 (PTH1R), we quantified trafficking of the receptors along with the mobilization and colocalization of coexpressed tagged β-arrestin2. This classification system allows for exclusion of cells with nonoptimal characteristics and calculation of multiple morphological and spatial parameters including receptor endosome formation, β-arrestin mobilization, colocalization, areas, and shape. Stimulated Class A and B receptors demonstrate dramatically different patterns with regard to β-arrestin interactions. The method provides high kinetic resolution measurement of receptor translocation, which allows for the identification of the fleeting β-arrestin interaction found with β2-AR agonist stimulation, in contrast to stronger mobilization and receptor colocalization with agonist stimulation of the PTH1R. Though especially appropriate for receptor kinetic studies, this method is generalizable to any dual fluorescence probe system in which quantification of object formation and movement is desired. These methodologies allow for quantitative, unbiased measurement of microscopy data and are further enhanced by providing real-time kinetics.

We present a case of severe acute pancreatitis in a 14-year-old boy that may have been caused by hyperparathyroidism. The clue to finding the parathyroid adenoma was the hypercalcaemia. Although the patient did have acute pancreatitis, no therapy had been effective until the discovery of the parathyroid adenoma. After the excision of the parathyroid adenoma, the function of the pancreas and serum calcium returned to normal. This result suggests a certain cause and effect relationship between hyperparathyroidism and acute pancreatitis.