Inhibitory avoidance learning inhibits ectonucleotidases activities in hippocampal synaptosomes of adult rats.
Several lines of evidence indicate that ATP may play an important role in Long-Term Potentiation. In this investigation we evaluated the effect of a memory task (step-down inhibitory avoidance) on the synaptosomal ecto-enzymes (ATP diphosphohydrolase and 5'-nucleotidase) involved in the degradation of ATP to adenosine. After the training session, a decrease in the ATPase (40%) and ADPase (29%) activities of ATP diphosphohydrolase as well as was a decrease in 5'-nucleotidase activity (31%) was observed in hippocampal synaptosomes of rats trained and killed immediately after training. In synaptosomes of rats killed 30 minutes after training, a decrease in ATPase activity (28%) was observed. In the test session, no significant changes were observed in the enzyme activities studied. These results provide new information about the activity of ecto-enzymes involved in nucleotide degradation and their possible participation in mechanisms of acquisition and modulation of memory processing.
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brasil.
C D
CD
Bonan
M M
MM
Dias
A M
AM
Battastini
R D
RD
Dias
J J
JJ
Sarkis
D015720:5'-Nucleotidase / Q000378:metabolism*; D000818:Animals; D001081:Apyrase / Q000378:metabolism*; D001362:Avoidance Learning; D006624:Hippocampus / Q000201:enzymology*; D008297:Male; D008568:Memory; D051381:Rats; D017208:Rats, Wistar; D013574:Synaptosomes / Q000201:enzymology*
D015720:5'-Nucleotidase; D001081:Apyrase