Factors Influencing the Concentration Gradient of Protein in Cerebrospinal Fluid12

Abstract

Radioiodinated serum albumin was administered intravenously to infants with communicating hydrocephalus. Four to 9 hours later, samples of ventricular, cisternal and lumbar cerebrospinal fluid were obtained within a 5 minute period. The specific activity was greatest in lumbar fluid, intermediate in cisternal fluid, and least in ventricular fluid. Samples of ventricular and lumbar cerebrospinal fluid were obtained from infants with communicating hydrocephalus and from children and adults with brain tumors. The relative concentrations of the albumin, globulin and prealbumin (X fraction) constituents in these fluids were determined by zone electro-phoretic analysis. The lumbar fluid in all cases contained relatively more albumin than globulin as compared with the ventricular fluid. The ventricular fluid contained more prealbumin (X fraction) than the lumbar fluid. These data suggest that the increasing concentration of protein from the ventricle to the lumbar region is a manifestation of greater permeability of the blood-cerebrospinal fluid barrier to proteins in the lumbar region.