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.
Bonan
C D
CD
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brasil.
Dias
M M
MM
Battastini
A M
AM
Dias
R D
RD
Sarkis
J J
JJ
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