US EPA

4936392 

Meetings & Symposia 

Abstract 

Chain-length specificity in ether lipid biosynthesis - Presence and metabolism of 1-docosanol in myelinating rat-brain 

Natarajan, V; Schmid, HHO 

1976 

English 

Long-chain alcohols are known to be the precursors of both alkyl and alk-1-enyl moieties of ether lipids in biological systems including the mammalian brain. In recent investigations on the levels of free longchain alcohols in rat brain at different stages of postnatal development, we detected relatively large amounts of 1-docosanol, comprising up to 20% of the total alcohols. Since rat brain ether lipids do not contain alkyl or alk-1 enyl moieties of more than 18 carbon atoms, the metabolism of docosanol relative to other fatty alcohols was investigated. Simultaneous intracerebral injection of (1-14cJdocosanol and [l-14c]octadecenol showed that both alcohols were oxidized to the corresponding fatty acids. However, only octadecenol served as substrate for alkylglycerol synthesis within a 24 hr period. Subcellular preparations of developing rat brain were used to study the reduction of fatty acids of different chain lengths to the corresponding alcohols, and the formation of the ether bond from such alcohols in vitro. Although previous work from this laboratory has shown that a variety of structural analogs of fatty alcohols can serve as alkyl donors in ether lipid biosynthesis, the present data indicate a distinct chain-length specificity for this reaction. 

172nd American Chemical Society Meeting 

San Francisco, CA 

August 29-Septemher 3, 1976