Altered activities of rat brain metabolic enzymes in electroconvulsive shock-induced seizures.

PURPOSE

Electroconvulsive shock (ECS) induces generalized seizure activity and provides an excellent experimental model for studying the effects of global electrical stimulation on various biochemical parameters. The aim of this work was to investigate the influence of a single or repeated ECS-induced seizures on rat brain metabolism.

METHODS

Experiments were carried out on female Hannover-Wistar rats divided into four groups: (a) the control group, which was intact; (b) the 1ECS group, which was killed 2 h after single ECS; (c) the 5ECS group with 24 h rest, which was killed 24 h after the fifth daily ECS; and (d) the 10ECS group with 48 h rest, which was given ECS every 48 h and killed 24 h after the tenth ECS. Activities of glutamate dehydrogenase (GLDH), aspartate-aminotransferase (AST), alanine-aminotransferase (ALT), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and creatine kinase (CK) in the frontal cortex, cerebellum, hippocampus, and pons/medulla regions were determined.

RESULTS

Increased AST, ALP, LDH, and CK activities were detected in all examined regions of the 1ECS and 5ECS groups. ALT activity was increased in both these groups, except in the hippocampus of the 5ECS group, where increased GGT activity was detected. In the hippocampus of 1ECS group, GLDH activity was decreased. Increased hippocampal AST and cortical CK activities, together with increased LDH activities in the cortex, cerebellum, and pons/medulla, were found.

CONCLUSIONS

ECS treatment induces region-specific changes in metabolic activity. Neither a 24-h nor a 48-h rest period between two ECSs was sufficient for complete brain recovery, although most of the observed increased enzyme activities present in 1ECS and 5ECS were not present in 10ECS.