Evaluation of therapy of goitrous goats from the functional status of the brain

摘要

Out of nine goats, which were clinically afflicted with endemic goitre (stage-3), six were treated orally with sodium thyroxine at 0.2 mg/day for 100 days. The remaining 3 goats were sacrificed as controls for the histopathology of the brains. Blood samples collected before thyroxine therapy revealed marked hypoglycemia (2.202±0.113 m mol/1), hyperlipidemia (10.336±0.915mmol/l) and hypercholesterolemia (7.594±0.309mmol/l). Thyroxine treatment resulted in a marked improvement in the concentrationsof these components as plasma levels were 4.404±0.467, 5.967±0.726 and 2.521±0.201 m mol/1, respectively. The plasma concentrations of epinephrine, nor-epinephrine and 5- HT also registered a significant (p<0.01) improvement from pretreatment values of 0.984±0.188, 2.366±0.198 and 8.822±1.751 u mol/1, to post treatment values of 5.704±1.758, 4.743±0.244 and 57.301 ±5.723 u mol/1, respectively. The efficacy of therapy was further reflected by a rise in the plasma thyroxine (39.38±6.82 to 110.937±9.140 n mol/1) and triiodothyronine (1.935±0.521 to 3.214±0.108 n mol/1) concentrations. The histopathology of the brains of the goitrous goats showed marked demyelination, neuronal degeneration, widening of the perineuronal space, mild satellosis and congestion in the white matter, satellosis, glyosis, congestion and neurophagia in the grey matter. Electroencephalograms from goitrous goats exhibited mixed alpha and distorted theta activity, which transformed to undulating alpha activity followingtreatment. The results suggested marked depression of the CNS activities due to goitre, which was partially restored following the treatment although the histological changes were irreversible.