Fig. 5. Meiotic germ cells are present transiently in XY gonads in the region of the rete testis. (A) SYN/COR and (B) H2AX were detected by immunofluorescence (green) in consecutive 8 µm sections; germ cells were labeled with PECAM1 (red). (C) A higher magnification of the region surrounded by the white rectangle in A. (D) At 15.5 dpc, apoptotic cells in this region were labeled with LysoTracker (magenta); germ cells were labeled with PECAM (red); the basal lamina of testis cords was stained for laminin (green). Arrows indicate germ cells. A, anterior; P, posterior; G, gonad; M, mesonephros; MT, mesonephric tubule; TC, testis cord.