Figure 3.

AAV4:BDNF and AAV4:noggin treatment did not result in increased cell death. Serial sections from AAV4:BDNF/noggin or AAV4:EGFP (n = 4 each) were subjected to TUNEL staining in combination with BrdU. (a) DNA degradation as identified by TUNEL was noted in cells with typical pyknotic morphology. (b) TUNEL⁺ cells were estimated by stereological cell counts throughout the OB, revealing more dying neurons in the AAV4:BDNF/noggin treated OBs than in their controls. (c) However, the fraction of TUNEL⁺ cells among all BrdU⁺ cells did not differ between the treated and control groups. Although the density of TUNEL⁺ cells was higher in AAV4:BDNF/noggin-treated rats (b, the fraction of TUNEL⁺ cells among all BrdU⁺ neurons was no different in the BDNF/noggin-treated rats than in their controls (c), suggesting that while increased neuronal recruitment to the OB was compensated for by increased death, the latter was unaffected by treatment. Scale: 20 μm; cells per mm³±s.e.m.