Behavioral and electroencephalographic manifestations of thioacetamide-induced encephalopathy in rats

Abstract

The aim of our study was to investigate the behavioral and electroencephalographic manifestations of thioaceta-mide-induced encephalopathy in rats. Male Wistar rats were divided among (i) control, saline-treated, and (ii) thioaceta-mide-treated groups (TAA300 (300 mg/kg body mass); TAA600 (600 mg/kg); and TAA900 (900 mg/kg)). The daily dose of thioacetamide (300 mg/kg) was administered intraperitoneally once (TAA300), twice (TAA600), or 3 times (TAA900), on subsequent days. Behavioral manifestations were determined at 0, 2, 4, 6, and 24 h, while electroencephalographic changes were recorded 22-24 h after the last dose. General motor activity and exploratory behavior, as well as head shake, auditory startle reflex, placement, and equlibrium tests were diminished in the TAA600 and TAA900 groups compared with the control, and were absent in the TAA900 group 24 h after treatment. Corneal, withdrawal, grasping, and righting reflexes were significantly diminished in the TAA900 group compared with the control. Mean electroencephalographic power spectra density was significantly higher in TAA300 and TAA600 and lower in the TAA900 group by comparison with the control. Only a score of 3 (mean dominant frequency ≤ 7.3 Hz and d relative power ≥ 45%) was observed in the TAA900 group. Thioacetamide induces encephalopathy in rats in a dose-dependent manner. A dose of 900 mg/kg TAA may be used as a suitable model of all stages of hepatic encephalopathy.