Penetration of Proteins in the Central Nervous System

Ribonucleases of human cerebrospinal fluid: detection of altered glycosylation relative to their serum counterparts

“…However, the resolution of CSF RNase species by phosphocellulose chromatography is much poorer than that of serum RNases, and a 18-30% higher NaCl concentration is required for elution of CSF RNases relative to their serum counterparts. This may be due in part to the presence of 200 times more protein in serum than in CSF (Lewin & Tradatti, 1976). The RNase 3 group was found to give rise to the largest activity peak in both serum and CSF, followed by the RNase 2 group and then RNase 4.…”

“…The composition of CSF, including protein content, is precisely regulated at the primary site of CSF secretion, the choroid plexus (Rapoport, 1976). The protein concentration of CSF is only 0.5% that of blood plasma, the source of most CSF protein (Lewin & Tradatti, 1976). However, the serum (or plasma) RNase/CSF RNase concentration ratios for normal individuals range from 4.9:1 to 20:1 (Rabin et al, 1977a), demonstrating that RNase activity represents a larger proportion of the total protein of CSF than of plasma.2 Human CSF RNases have not been investigated as thoroughly as those of human blood serum or urine.…”