Introduction. Diabetic retinopathy pathogenesis includes mechanisms of the deterioration of retinal neurons activity, which is expressed in electroretinographic (ERG) manifestations. It is reasonable to register ERG in diabetic rats under condition of treatment with antioxidants and anti-VEGF drug.
The aim was to investigate the ERG peculiarities in rats with streptozotocin-induced diabetes under conditions of treatment with alpha-lipoic acid and avastin.
Methods of investigations. In Wistar rats diabetes have been modeled via i. p. streptozotocin administration (50.0 mg/kg, i. p.). In 0.5 months from the moment of streptozotocin injection and during next two months treatment with alpha-lipoic acid (20.0 mg/kg, i. p., daily) and avastin (0.5 mg, intravitreally, monthly) started with the consequent ERG registration.
Results. The increase of latency of β-wave in ERG by 10.4% along with the reduction of its amplitude 2.24 times pertained to intact rats was seen in diabetic animals (P<0.05). At the same time the latency of α-wave was greater by 25.1% (P<0.05), while the dynamics of its amplitde was slower 2.47 times (P<0.05). The oscillatory potentials W2 and W3 latency increased by 42.5% and 42.8% (P<0.05), while their amplitude were reduced 5.0 and 3.37 times correspondently when compared to control group (P<0.05). Treatment with alpha-lipoic acid was followed by the increase of β-wave amplitude by 45.5% (P<0.05), while the amplitude of W3 increased 1.4 times (P<0.05). The same treatment combined with avastin was resulted in the increasing of β-wave amplitude, which exceeded that one registered in alpha-lipoic-treated rats by 32.8% (P<0.05), increasing of the dynamic of amplitude of α-wave 2.2 times pertained to diabetic rats (P<0.05), decreasing of the latency of W2 by 28.1% (P<0.05) with the increasing of its amplitude 3.3 times and the reduction of the W3 latency by 24.6% (P<0.05), аlong with the increasing of its amplitude 2.2 times (P<0.05).
Conclusions: sreptozotocin-induced diabetes is followed by ERG deterioration mainly manifested in the increase of latency and reduction of amplitude of α-, β-waves, and oscillatory W2 and W3 potentials. Treatment with alpha-lipoic acid prevented diabetes-induced deterioration and this effect is more pronounced under condition of simultaneous treatment with avastin.