Figure 1: No significant change in expression levels of mRNAs for sex steroidogenic enzymes and receptor (A: 5a-reductase type1, B: 5areductase type2, C: AR and D: StAR) in the female hippocampus across the estrous cycle. Upper panels show representative PCR images and lower panels show statistical comparisons. In each images, from left to right, size marker (100 bp ladder) (M), male hippocampus (male), female hippocampus at Pro (P), Est (E), D1 (D1), D2 (D2), and OVX female rats (OVX), the sample without template DNA as negative control (Nc). F o r each enzyme, the RT-PCR products for mRNAs are visualized with ethidium bromide staining on the top of each panel. As an internal control, the ethidium bromide staining of GAPDH is shown on the bottom of each panel. PCR was performed by using cDNA made by reverse transcription from 100 ng of hippocampal total RNA. Statistical comparisons show no estrous cycle-dependent changes of mRNA expression for sex-steroidogenic enzymes. The vertical axis indicates the expression level for each enzyme calculated from the intensity of EB bands. Each value is mean ± S.E.M. Data are taken from duplicate determinations for each rat of total 4 rats.