Table 3. Retinal protection conferred by individual and combination therapies targeting GPCRs.

Either BRM, MTP, or TAM was administered individually at a subeffective dose to Abca4^−/−Rdh8^−/− mice or in a combined pretreatment consisting of two or three of these compounds, each at its subeffective dose. Doses for either single or combined pretreatments were 0.1, 1, and 0.05 mg/kg bw for BRM, MTP, and TAM, respectively. Protection was assessed as morphological preservation of the retina by OCT imaging 7 days after exposure to bright light. Complete protection represented the retinas with intact ONL morphology similar to those of mice unexposed to bright light, with ONL thicknesses of ≥50 μm at 0.45 mm away from the ONH in the temporal retina. No protection represented retinas exhibiting morphology similar to that of light-exposed and vehicle-treated mice, with ONL thickness of ≤20 μm at 0.45 mm away from the ONH in the temporal retina. Partial protection defined retinas manifesting a reduction in the thickness of the ONL between 20 and 50 μm measured 0.45 mm away from the ONH in the temporal retina. This was followed by exposure to bright light and OCT imaging performed 7 days later. Percentages of mice manifesting no protection of retinal structures were calculated for each condition.

Drug	Percent of mice with complete protection	Percent of mice with no protection
BRM	16.7	66.7
MTP	25	41.7
TAM	16.7	58.3
DOX	0	100
BRM + MTP	33.3	25
BRM + TAM	42.86	42.86
MTP + TAM	41.7	16.7
BRM + MTP + TAM	87.5	4.17
BRM + DOX	50	16.7
MTP + DOX	33.3	41.7
BRM + MTP + DOX	80	5