Reduction of hippocampal Na+, K+-ATPase activity in rats subjected to an experimental model of depression.
The effect of a model of depression using female rats on Na+, K+-ATPase activity in hippocampal synaptic plasma membranes was studied. In addition, the effect of further chronic treatment with fluoxetine on this enzyme activity was verified. Sweet food consumption was measured to evaluate the efficacy of this model in inducing a state of reduced response to rewarding stimili. After 40 days of mild stress, a reduction in sweet food ingestion was observed. Reduction of hippocampal Na+, K+-ATPase activity was also observed. Treatment with fluoxetine increased this enzyme activity and reversed the effect of stress. Chronic fluoxetine decreased the ingestion of sweet food in both groups. This result is in agreement with suggestions that reduction of Na+, K+-ATPase activity is a caracteristic of depressive disorders. Fluoxetine reversed this effect. Therefore it is possible that altered Na+, K+-ATPase activity may be involved in the pathophysiology of depression in patients.
Gamaro
Giovana D
GD
Departamento de Bioquimica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-Anexo. CEP: 90035-003. Porto Alegre, RS, Brazil.
Streck
Emilio L
EL
Matté
Cristiane
C
Prediger
Martha E
ME
Wyse
Angela T S
AT
Dalmaz
Carla
C
D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology; D002908:Chronic Disease; D003863:Depression / Q000201:enzymology* / Q000209:etiology; D004435:Eating; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D012201:Reward; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013312:Stress, Physiological / Q000150:complications; D013570:Synaptic Membranes / Q000378:metabolism
D000928:Antidepressive Agents; D005473:Fluoxetine; D000254:Sodium-Potassium-Exchanging ATPase