Creatine transport in cultured cells of rat and mouse brain.
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.
Möller
A
A
Physiologisch-chemisches Institut der Universität, Tübingen, F.R.G.
Hamprecht
B
B
D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D001667:Binding, Competitive; D001692:Biological Transport / Q000187:drug effects; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D002478:Cells, Cultured; D003404:Creatinine / Q000378:metabolism*; D005910:Glioma; D006146:Guanidines / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D009447:Neuroblastoma; D009474:Neurons / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D011422:Propionates / Q000494:pharmacology; D051381:Rats; D012964:Sodium / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D006146:Guanidines; D011422:Propionates; D010042:Ouabain; D012964:Sodium; D003404:Creatinine; D000254:Sodium-Potassium-Exchanging ATPase; C005775:guanidinopropionic acid