This excellent report uses a previously utilized protocol to up-regulate the expression of the GABAergic markers in granule cells. The authors cite Gutierrez (TiNS 2005) as the source and mention that their results "support the correspondence between the in vitro and in vivo phenotype", implying that we only worked in in vivo conditions. For clarification purposes, I wanted to mention that the full description of the protocol appeared in a paper that was in press at the time the TiNS review was published, where both in vivo and in vitro experiments are described. See Gomez-Lira et al. J.Neurosci. 25:6939–6946, 2005. An important issue to be resolved though is whether newborn granule cells in the adult rat do use GABA as a fast-acting neurotransmitter. Although we suggest that this is the case, a direct proof of this is still missing.
