Figure 3.

Retinoid and primary amine effects on intracellular calcium. A, cellular calcium imaging after treatment with DMSO or with 30 μm 11-cisRAL, 9-cisRAL, atRAL, atROL, and A2E. B, condensation reaction of atRAL with primary amines resulting in N-retinylidene Schiff base formation. C, dose–response effects of emixustat, MB-001, and MB-002 on calcium influx due to atRAL quenching. The dose–response curves of primary amine compounds emixustat and MB-001 along with the hydroxyl-conjugated MB-002 compound are plotted by intensity (INT) ratio of the fluo-3–Ca²⁺ complex. Concentrations tested were in the range of 0.8–400 μm. Error bars, S.D. of triplicate readings.