[Protective effect of Huangban Granule against light-induced retinal damage in rats]

To observe the protective effect of Huangban Granule, a compound of traditional Chinese herbal medicine, on rats with retinal damage induced by light.

A total of 24 male Sprague-Dawley (SD) rats were randomly divided into normal control group, untreated group and Huangban Granule group. Retinal light damage was induced by exposure to constant white fluorescent light for 5 hours at an illumination of 2,800 Lux. The Huangban Granule was given 10 days before light exposure until the animals were sacrificed in Huangban Granule group, and an equal volume of distilled water for the rats in untreated group. Electroretinogram (ERG) was recorded in all animals 2 weeks after light exposure and the animals were sacrificed for histopathological examination of retina. The outer nuclear layers (ONLs) on the superior and inferior retina were counted.

Fourteen days after light exposure, the ONLs on the superior retina were 3 to 6 in the untreated group and 7 to 9 in treatment group. There were 9 to 11 layers in normal group. The mean number of ONLs in the untreated group (4.68+/-1.64) was less than that in the treatment group (8.23+/-1.35) (P<0.01). B-wave amplitudes were (319.38+/-71.96) muV and (135.16+/-42.30) muV in Huangban Granule group and the untreated group respectively (P<0.01). A-wave amplitudes were (184.63+/-47.23) muV and (83.35+/-27.75) muV (P<0.01), and oscillatory potential amplitudes were (239.38+/-20.19) muV and (125.44+/-26.23) muV (P<0.01) respectively in the two group. There was no significant difference in implicit times of a-wave and b-wave among the three groups.

Huangban Granule obviously protects both function and morphology of the retina from light-induced retinal damage in rats.