Figure 3.

Rapid rod cell death in stage 53 transgenic XOPNTR tadpoles treated with metronidazole. (A–C) Retinal sections were labeled to detect apoptotic cells (TUNEL; red) and all cell nuclei (DAPI; blue). Wild-type (A) and transgenic (B, C) tadpoles were left untreated (B) or were treated with Mtz (A, C) for 1 day. (D–D″) To identify the class of apoptotic cells in the ONL, retinal sections were stained for TUNEL (D; red) and the cone marker calbindin (D′; green). D and D′ are merged in D″. Scale bars: 200 μm (A–C); 25 μm (D–D′). Arrowheads: TUNEL-positive cells.