Efficacy of Methylprednisolone in Aconite Induced Myelo-optic Neuropathy in the Rabbit

ABSTRACT

Studies in animals indicate that aconitine or aconite has toxic effects in the visual system of a rabbit model. Such a toxic effects causes myelo-optic neuropathy in the visually evoked cortical potential(VECP) and histopathologic studies. Whether the administration of intravenous high-dose of methyprednisolone(MP) in the myelo-optic neuropathy caused by aconitine(1.5ml/kg, equivalent to 0.7mg/kg of aconitine) is experimentally effective remains uncertain. The group treated with MP(daily 30mg/kg X 2 for 3 days followed by 15mg/kg for 3 days) in addition to aconite was compared with the aconite alone group and the normal control group. In the MP treated group, increased recovery of onset latency, peak latency, and amplitude in VECP in comparision with the aconite alone group was recorded at 2 weeks (p<0.05). The MP treated group in comparision with the normal control group showed a significant delay in onset latency at 1 month and 2 months(p<0.05). But, the amplitude in both the MP treated group and the aconite alone group increased at 2 months and did not show a significant difference in comparision with the normal group(p<0.05). In histopathologic study, pathologic findings of myelin sheath in the MP treated group were less severe than in the aconite alone group generally. The true benefit of high-dose MP was at least clear within 2 weeks. The authors conclude that treatment with intravenous high-dose MP immediate after aconite injection may have some beneficial effects in recovery of neurologic function although such a treatment do not have the definite recovery in aconite induced myelo-optic neuropathy.