Cytochrome P450–Dependent Renal Arachidonic Acid Metabolism in Desoxycorticosterone Acetate–Salt Hypertensive Mice
Autor: | Ralf Dr. Neunaber, Anna Franca Milia, Wolfgang Schneider, Friedrich C. Luft, Eva Kärgel, Bettina Erdmann, Volkmar Gross, Wolf-Hagen Schunck, Horst Honeck |
---|---|
Rok vydání: | 2000 |
Předmět: |
Male
medicine.medical_specialty Mice Inbred Strains Sodium Chloride Hydroxylation Kidney Nephrectomy Mixed Function Oxygenases Mice chemistry.chemical_compound Cytochrome P-450 Enzyme System Microsomes Internal medicine Hydroxyeicosatetraenoic Acids Internal Medicine medicine Animals Lovastatin RNA Messenger Desoxycorticosterone Chromatography High Pressure Liquid In Situ Hybridization Hypolipidemic Agents Arachidonic Acid Bezafibrate biology Chemistry Cytochrome P450 Metabolism medicine.anatomical_structure Endocrinology Hypertension biology.protein Microsome Arachidonic acid Cytochrome P-450 CYP4A Hydroxymethylglutaryl-CoA Reductase Inhibitors NADP medicine.drug |
Zdroj: | Scopus-Elsevier |
ISSN: | 1524-4563 0194-911X |
Popis: | Abstract —Cytochrome P450 (P450)-dependent arachidonic acid metabolites may act as mediators in the regulation of vascular tone and renal function. We studied arachidonic acid hydroxylase activities in renal microsomes from normotensive NMRI mice, desoxycorticosterone acetate (DOCA)-salt hypertensive mice, and DOCA-salt mice treated with either lovastatin or bezafibrate, both of which improve hemodynamics in this model. Control renal microsomes had arachidonic acid hydroxylase activities of 175±12 pmol · min −1 · mg −1 . The metabolites formed were 20- and 19-hydroxyarachidonic acid, representing ≈80% and ≈20% of the total hydroxylation. Treatment with DOCA-salt resulted in significantly decreased hydroxylase activities (to 84±4 pmol · min −1 · mg −1 ) of the total microsomal P450 content and a decrease in immunodetectable Cyp4a proteins. Lovastatin had no effect on these variables, whereas bezafibrate increased arachidonic acid hydroxylase activities to 163±12 pmol · min −1 · mg −1 . In situ hybridization with probes for Cyp4a-10, 12, and 14 revealed that Cyp4a-14 was the P450 isoform most strongly induced by bezafibrate. The expression was concentrated in the cortical medullary junction and was localized predominantly in the proximal tubules. In conclusion, these results suggest that the capacity to produce 20-hydroxyarachidonic acid is impaired in the kidneys of DOCA-salt hypertensive mice. Furthermore, bezafibrate may ameliorate hemodynamics in this model by restoring P450-dependent arachidonic acid hydroxylase activities. Lovastatin, on the other hand, exerts its effects via P450-independent mechanisms. |
Databáze: | OpenAIRE |
Externí odkaz: |