Effect of CDP-choline on brain acetylcholinesterase and Na(+), K(+)-ATPase in adult rats.
OBJECTIVE
The aim of this work was to investigate the effect of different cytidine-5'-diphosphocholine (CDP-choline) concentrations (0.1-1 mM) on acetylcholinesterase (AChE), (Na(+),K(+))-ATPase and Mg(2+)-ATPase activities in homogenates of adult rat whole brain and in pure (nonmembrane bound) enzymes.


METHODS
Tissues were homogenized, centrifuged at 1000 xg for 10 min, and in the supernatant AChE activity and Na(+),K(+)-ATPase, Mg(2+)-ATPase activities were determined according to Ellman's method and Bowler's and Tirri's, respectively.


RESULTS
After a 1-3 h CDP-choline preincubation, this substance induced a maximal stimulation of 20%-25% (p < 0.001) for AChE and 50-55% (p < 0.001) for Na(+), K(+)-ATPase, but it did not influence Mg(2+)-ATPase activity. One mM acetylcholine (ACh) resulted in an approximately 18% (p < 0.001) AChE inhibition by excess substrate in the brain homogenate, while 0. 01 mM noradrenaline did not influence Na(+),K(+)-ATPase activity.


CONCLUSIONS
CDP-choline can stimulate brain AChE and Na(+), K(+)-ATPase independently of ACh and noradrenaline. This enzymatic stimulation may be due to the transformation of CDP-choline to membrane phophatidylcholine. The above data could explain in part the clinical effects of this substance in some neuronal disturbances.
Plataras
C
C
Department of Experimental Physiology, University of Athens, Medical School, Athens, Greece.
Tsakiris
S
S
Angelogianni
P
P
D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000110:Acetylcholinesterase / Q000187:drug effects*; D000251:Adenosine Triphosphatases / Q000187:drug effects; D000818:Animals; D001921:Brain / Q000201:enzymology*; D017301:Ca(2+) Mg(2+)-ATPase / Q000187:drug effects; D002794:Choline / Q000494:pharmacology; D003562:Cytidine / Q000494:pharmacology; D003566:Cytidine Diphosphate Choline / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D009638:Norepinephrine / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000187:drug effects*; D013552:Swine; D013997:Time Factors
D003566:Cytidine Diphosphate Choline; D003562:Cytidine; D000110:Acetylcholinesterase; D000251:Adenosine Triphosphatases; D017301:Ca(2+) Mg(2+)-ATPase; C035123:magnesium sodium ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D002794:Choline; D000109:Acetylcholine; D009638:Norepinephrine