Effects of inhibitory avoidance training and/or isolated foot-shock on ectonucleotidase activities in synaptosomes of the anterior and posterior cingulate cortex and the medial precentral area of adult rats.
Compelling evidence has indicated the involvement of extracellular ATP and adenosine in the mechanisms of synaptic plasticity and memory formation. In the present study, adult rats were trained in a step-down inhibitory avoidance task (IA) or submitted to isolated foot-shock (IF) (0.4 mA) before measuring ectonucleotidase activities in the synaptosomes of the anterior and posterior cingulate cortex (AC and PC, respectively) and the medial precentral area (Fr2). IA increased ATP and ADP hydrolysis immediately after training in the synaptosomes of PC and AC, respectively, (P<0.05). Foot-shock (independent of occurring during IA or IF) increased ATP hydrolysis in synaptosomes of AC and Fr2 immediately after application and decreased AIP hydrolysis in AC 90 min after application (P<0.05). Foot-shock (independent of occurring during IA or IF) increased ATP hydrolysis in PC immediately and 90 min after application, and in Fr2, but only immediately after application (P<0.05). These results suggest that the ectonucleotidase pathway responds to a mild foot-shock in AC, PC and Fr2 and may be involved in memory consolidation of step-down inhibitory avoidance in the cingulate cortex.
Pereira
Grace Schenatto
GS
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-ANEXO, 90035-003, Porto Alegre RS, Brazil.
Mello e Souza
Tadeu
T
Battastini
Ana Maria Oliveira
AM
Izquierdo
Iván
I
Sarkis
João José Freitas
JJ
Bonan
Carla Denise
CD
D000241:Adenosine / Q000096:biosynthesis / Q000502:physiology; D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D002540:Cerebral Cortex / Q000201:enzymology*; D004597:Electroshock; D006868:Hydrolysis; D008297:Male; D008568:Memory / Q000502:physiology; D009708:Nucleotidases / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000201:enzymology* / Q000523:psychology*; D013347:Subcellular Fractions / Q000201:enzymology; D013574:Synaptosomes / Q000201:enzymology*
D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D009708:Nucleotidases; D000241:Adenosine