Specific RNase isoenzymes in the XXXX central nervous system.

@entity1 @entity6220 @entity11153 @entity19 @entity1735 @entity8866 @entity15 @entity35 @entity70986 @entity291
After inactivation of RNase inhibitor by @entity8866 , total alkaline RNase activity was found to be two fold higher in white matter as in grey matter extracts from @entity1 brain tissue. This activity was lower in @entity1 purified myelin. Two @entity1 cerebrospinal fluid (CSF) RNase isoenzymes of group 3 (a minor one, @entity11153 .1, and a major one, @entity11153 .2) were found to be present in @entity1 grey and white matter extracts and in purified myelin, but absent in human serum, peripheral nerve, liver, and spleen extracts. A RNase isoenzyme similar to central nervous system (CNS) @entity11153 .2 was present in @entity1 kidney extracts but it differed in its @entity1735 structure. RNase isoenzymes 3.1 and 3.2 were not found in @entity19 , @entity35 , and @entity291 brains. Thus, @entity70986 .2 seem specific to @entity1 CNS. RNases of group 3 are the predominant RNase isoenzymes in CSF and one of the two predominant RNase groups in brain tissue. However, the proportion of RNases of group 3 is different in CSF and in brain extracts: RNases 3.1-3.2 are the major constituents of group 3 RNases in brain tissue, while another RNase isoenzyme of group 3, @entity11153 .0, which is more glycosylated than RNases 3.1-3.2, is only a minor part of RNase of group 3 in brain extracts. Conversely, RNases 3.1-3.2 are lower or equivalent to @entity11153 .0 in control CSF since the ratio of RNases 3.1-3.2 to @entity11153 .0 did not exceed 1.0. This ratio decreased in pathological CSF including @entity15 or @entity6220 that were free of transudation phenomena. In conclusion, CSF RNases 3.1-3.2 seem to originate in brain tissue and could be markers of RNA catabolism from brain cells.
