Semiquantitative PCR analyses of gene expression in Aqp9-/- and WT mice brain.

A) Semi-quantitative Real-Time PCR revealed significantly higher Aqp9 mRNA levels in the midbrain and striatum than in the neocortex. The level of Aqp9 mRNA in neocortex is 59% of that in midbrain (p = 0.002). The level of Aqp9 mRNA in the Aqp9-/- mice was close to the detection limit (n = 7 for each genotype). B) Representative DNA agarose gel electrophoresis of midbrain samples from WT and Aqp9-/- mice (upper panel), and of three different regions in WT mice (lower panel). These data support the PCR analysis in A. C) In order to rule out that the reduced dopaminergic cell loss in the Aqp9-/- mice could be attributed to compensatory up- or downregulation of other genes, an analysis was done of the expression levels of Aqp4, Gfap, Kir4.1, mTOR, Prph, Cat, Ppard, Slc6a3 (DAT), Drd2, Bcl2, Bax and Sod2. The relative levels of these transcripts did not differ between Aqp9-/- (n = 7) and WT animals (n = 7). D-H). For selected genes the expression levels were analyzed in the treated and untreated hemispheres. In both groups of animal, the transcript levels of Drd2 were lower in the striatum on the injected side than in the striatum on the contralateral side (E). In contrast, in both groups of animals, the level of Bax was higher in the ipsilateral striatum than in the contralateral one (H). The values indicated in the graphs for DAT, Bcl2 and Sod2 show the values for midbrain, and the values for Drd2 are for striatum. All values are relative to the values for the corresponding samples from the control hemisphere of the saline treated mice. Bars are mean ± 2 SEM; **p<0.005.