Precursors for Cholesterol Synthesis (7-Dehydrocholesterol, 7-Dehydrodesmosterol, and Desmosterol): Cholesterol/7-Dehydrocholesterol Ratio as an Index of Development and Aging in PNS but Not in CNS |
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Authors: | J. M. Bourre,M. Clé ment,D. Gé rard,R. Legrand,J. Chaudiè re |
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Affiliation: | INSERM U. 26, Hôpital Fernand Widal, Paris;Centre de Recherches, Roussel-Uclaf, Romainville, France |
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Abstract: | In rat sciatic nerve, the 7-dehydrocholesterol content decreased dramatically during the postnatal period and slowly during adulthood and aging. In contrast, the 7-dehydrodesmosterol content peaked at 14 days and was nearly undetectable after 60 days. The desmosterol content peaked at 21 days and was nearly undetectable after 1 year. The cholesterol content increased up to 21 days and remained nearly constant thereafter. In brain (in contrast to sciatic nerve), 7-dehydrodesmosterol and desmosterol contents decreased dramatically during development and slightly during adulthood and aging; the 7-dehydrocholesterol content peaked at 21 days and remained constant during aging. Only 7-dehydrocholesterol was dramatically more concentrated in PNS than in CNS. In brain, the cholesterol/7-dehydrocholesterol ratio increased during development and remained stable after 6 months. In contrast, in sciatic nerve, this ratio continuously increased during development and aging (950-fold between 5 days and 18 months). Thus, the cholesterol/7-dehydrocholesterol ratio is a useful biochemical index of development and aging in the PNS. |
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Keywords: | Cholesterol 7-Dehydrocholesterol 7-Dehydrodesmosterol Desmosterol Brain Sciatic nerve PNS CNS Development Aging |
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