Research PapersRegional Distribution of Individual Forms of Cytochrome P450 mRNA in Normal Adult Human Brain
Section snippets
Tissue
Normal human brain was obtained, with permission, from autopsies carried out in the Department of Pathology, University of Aberdeen. The clinical details and causes of death are summarised in Table 1. None of the patients displayed any sign of neurological disease and they were non-smokers who had not been treated with any drugs known to induce P450 expression. All the brains appeared normal at post-mortem examination and tissue samples were obtained within 24 hr of death from the following
Results
All the samples of brain showed the presence of β-actin mRNA (Fig. 1) and thus were subjected to PCR for individual P450s. The presence and distribution of individual P450s in the specific regions of the five different brains was similar. CYP1A1 mRNA was detected in cerebellum, mid brain, basal ganglia, frontal cortex and temporal cortex but was not detected in either the medulla or pons while CYP1A2 mRNA was detected only weakly in the basal ganglia and not in any of the other regions of
Discussion
The P450s have a critical role in the activation and deactivation of many toxic foreign chemicals and the relative expression of specific forms of cytochrome P450 in a particular tissue is important in determining the toxicity of an individual chemical [12]. It is therefore important to determine the expression of different forms of P450 in specific areas of the brain to further understand the effect of toxic substances in brain. In rodent brain multiple forms of P450 have been shown to be
Acknowledgements
We thank The Association for International Cancer Research and Tenovus-Scotland for financial support.
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