[The effect of hypothermia on kinetic characteristics of the rat brain synaptic membrane Na,K-ATPase].
The effect of profound hypothermia (acute or prolonged) on Km for ATP, Vm and strophanthine K affinity to Na,K-ATPase in the rat brain synaptosomal membranes was investigated. The temperature dependence of Na,K-ATPase activity in temperature range 5-40 degrees C was also studied. Hypothermia decreases Km and Vm, and increases affinity of strophanthine K to the enzyme. There are two linear sections in Arrhenius plots ofNa,K-ATPase activity. Hypothermia does not change position of the break point in Arrhenius plots. The mechanisms and biological significance of the changes revealed are discussed.
Klichkhanov
N K
NK
Khalilov
R A
RA
Meĭlanov
I S
IS
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002316:Cardiotonic Agents / Q000494:pharmacology; D007035:Hypothermia / Q000201:enzymology*; D007700:Kinetics; D008297:Male; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase; D013328:Strophanthins / Q000494:pharmacology; D013570:Synaptic Membranes / Q000201:enzymology*
D002316:Cardiotonic Agents; D013328:Strophanthins; D000254:Sodium-Potassium-Exchanging ATPase; C029082:strophanthin K