ABSTRACT
The pattern of free sterols occurring in the cerebral white matter was studied in an experimental model of global ischemia that was induced in rats by means of the method described by KORPACHEV et al. (1982). Sterol isolation, separation and identification was accomplished by suitable extraction procedures followed by gas-chromatography-mass spectrometry of the purified sterol extracts. It has been shown that the percentage of lanosterol happened to decrease sharply following the ischemic state and other sterols, typically occurring in maturating brains and absent in the control brain specimens from adult rats, such as 4,4-dimethylcholesterol, 4,4-dimethylcholest-5,8,24-triene-3 beta-ol and 4,4,14-trimethylcholest-5,8-diene-3 beta-ol happened to appear. The appearance of these forms of free sterols in the postischemic brain is interpreted as a biochemical exponent of regeneration processes occurring in the white matter membranes following the injury suffered during the experimental heart arrest.
Subject(s)
Brain Ischemia/metabolism , Cerebral Cortex/metabolism , Reperfusion Injury/metabolism , Sterols/metabolism , Animals , Chemical Fractionation , Cholesterol/analysis , Cholesterol/metabolism , Gas Chromatography-Mass Spectrometry , Lanosterol/analysis , Lanosterol/metabolism , Rats , Rats, Wistar , Sterols/chemistry , Sterols/isolation & purificationABSTRACT
Free sterol content was determined in the late period of development of the rat brain using the method of gas chromatography-mass spectrometry. The results obtained have shown that the free sterol pattern is very unstable in course of late period of ontogenic development. In contrast to young adult rats, in which apart from cholesterol only trimethylcholestenon and trace amounts of desmosterol were visible, in the brain of 1 and 2 years old rats some new sterols are appearing. There are cholestadien, cholest-5-en-3-on, 4 methyl-cholesten, cholest-5-en-3-ethoxy and 4,4,14-trimethyl-5-alpha-cholest-24-en-3-en. There are also qualitative differences in the structure of some sterols (various isomers) between both groups of late development. These changes, indicating some transformation of cellular membranes seem to be the result of biologically programmed late ontogenic development.
