Normalized calcium signals for the 96 fractions of herbal extracts using the cytofluor multi-well plate reader. The calcium assay was performed in 96-well plates containing HEK293 cells stably expressing the EP1 receptor and incubated with Fluo8-AM dye. The water soluble supernatants (5 μL) of the herbal extracts were added to the stable EP1 HEK293 cells and the calcium signals were determined. To minimize loss of signal, the experiment was performed four wells at a time. The normalized calcium signal was calculated by subtracting the inherent fluorescence of the extract in the background, where n = 3. The results were presented as four individual graphs showing the extracts, as indicated. The top 17 extracts with significantly increased calcium signal (moderate ≥5000, high ≥20000) are listed in panel I. The normalized calcium signals for the remaining herbal extracts (18-96) with little or no activity (≤5000) are shown in panel II.