Regional Distribution of Cytochrome P-450 in the Rat Brain: Spectral Quantitation and Contribution of P-450b,e and P-450c,d

摘要: : The cytochrome P-450 (P-450) content of different regions the rat brain was measured after partial purification enzyme from homogenates, and quantitative contribution P-450b,e P-450c,d to assessed by Western immunoblotting immunohistochemistry using rabbit antibodies raised against purified hepatic P-450b P-450c (anti-P-450b anti-P-450c, respectively). could be quantitated its reduced CO difference spectrum chromatography homogenates on p-chloroamphetamine-coupled Sepharose. yield whole 90 ± 19 pmol/g tissue, which is ∼ 1% level in liver microsomes control rats. amount recovered olfactory lobes, hypothalamus, thalamus, striatum, cerebral cortex, brainstem varied between 40 100 tissue. cerebellum a region exceptionally high content, with yields up 400 pmol/g, whereas substantia nigra yielded only 16–20 pmol/g. Immunohistochemical studies anti-P-450b anti-P-450c revealed intense staining limited number cells both thalamus anti-P-450c. In cerebellum, stained Bergmann glial together their radial processes. Individual granular cell layer were also stained. There no Purkinje cells. gave weak certain astroglia, but there neuronal somata. immunoblots isolated confirmed distribution observed immunohistochemistry. Of all examined, detected obtained thalamus. However, quantitation bands 125I-labeled protein A that these forms account for <1% This low reflected ethoxycoumarin O-deethylase activity From studies, it concluded are multiple highly selectively localized Furthermore, most remains uncharacterized.