Abstract: The invention provides a novel high throughput functional assay for certain agonist-activated receptors, including Alpha 1A, Alpha 2A, H1, 5HT1A, 5HT2A, D2 and D3 receptors. The assay method of the invention uses an elevated temperature and a cell line that stably expresses both the receptor and the promiscuous G protein G↑15 wherein agonist-induced intracellular Ca2+ release was monitored by a Fluorometric Imaging Plate Reader (FLIPR). The magnitude of the agonist-induced response was dramatically enhanced by performing the assay at an elevated temperature, rather than at room temperature. The novel assay of the invention is useful for selecting compounds which are effective in the treatment of disorders related to the activation of certain neuroreceptors.