Uptake of D-serine by synaptosomal P2 fraction isolated from rat brain

We have demonstrated that the crude synaptosome P2 fraction prepared from t he rat brain is able to accumulate [H-3]D-serine in a saturable, temperatur e-dependent and partially sodium- and potassium-dependent manner with an af finity of a hundred micromolar range. The inhibition profile of D-serine ac cumulation by various amino acids is different from those of uptake systems reported for glycine and other amino acids. The present data suggest that the endogenous D-serine may be taken up mainly through a carrier-mediated t ransport system to regulate its extracellular concentration in the mammalia n brain. (C) 2001 Wiley-Liss, Inc.