Möller A, Hamprecht B
Physiologisch-chemisches Institut der Universität, Tübingen, F.R.G.
J Neurochem. 1989 Feb;52(2):544-50. doi: 10.1111/j.1471-4159.1989.tb09154.x.
Astroglia-rich cultures derived from brains of newborn rats or mice use a transport system for the uptake of creatine. The uptake system is saturable, Na+-dependent, and highly specific for creatine and Na+. Kinetic studies on rat cells revealed a Km value for creatine of 45 microM, a Vmax of 17 nmol x h-1 x (mg of protein)-1, and a Km value of 55 mM for Na+. The carrier is competitively inhibited by guanidinopropionate (Ki = 15 microM). No such transport system was found in neuron-rich primary cultures from embryonic rat brain. It is hypothesized that creatine transport is an astroglial rather than a neuronal function.
