Brain uptake and CNS levels of 1-(2-chloroethyl)-1-nitroso-3-(2-hydroxyethyl)urea (HECNU).

The uptake of 14C-labeled 1-(2-chloroethyl)-1-nitroso-3-(2-hydroxyethyl)urea (HECNU) into the brain was investigated in the rat after intracarotid injection according to the method of OLDENDORF, as well as in cisternal cerebrospinal fluid obtained by suboccipital puncture after i.v. injection of the drug. The brain uptake index was 31.9 +/- 2.9%. Cerebrospinal fluid/blood quotients after i.v. injection were 0.82 at 10 min and 1.10 at 60 min. The results of both methods clearly show that HECNU, in spite of its hydrophilic property, easily penetrates the blood-brain barrier.