title: Effects of Rubus coreanus extract on visual processes in bullfrog's eye.
abstract: BACKGROUND
  The fruit of Rubus coreanus (Rosaceae) is traditionally used as an aphrodisiac, astringent, restorative and tonic in Asian countries. It is advised for treating diseases related to liver, kidney and urinary dysfunction, premature greying, blurred vision, infertility, impotence and premature ejaculation. Additionally, there is a long history of different parts of the plants being used in the treatment of ophthalmic diseases. However, no scientific studies have been undertaken to determine the effects of Rubus coreanus in visual processes of the vertebrate retina.
  
  
  OBJECTIVE
  The purpose of the present study was to investigate the positive effects of Rubus coreanus extracts on visual processes in the vertebrate's eye.
  
  
  METHODS
  Electroretinogram (ERG) techniques were used to record the responses from a bullfrog's eye cup preparations. Active pharmacological agents were used to block specific receptors in the retina and to leave others unaffected. Lipid peroxidation in the retina was generated by adding FeSO(4)+Na-ascorbate.
  
  
  RESULTS
  It was observed that both dark- and light-adapted ERG b-wave peak amplitude significantly increases with Rubus coreanus treatment. It was found that Rubus coreanus acts as a retinal neural antagonist but not as GABA receptor antagonist. Rubus coreanus treatment lowered the duration of rhodopsin regeneration. The results obtained indicated that Rubus coreanus protects against lipid peroxidation drop off ERG amplitude in retina.
  
  
  CONCLUSIONS
  Based on results obtained, it is suggested that Rubus coreanus can potentially improve visual sensitivity and can be used to treat pathophysiological conditions of eye.
authors.affiliation: School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, 1370 Sangeok-dong, Buk-ku, Taegu 702-701, Republic of Korea.
authors.forename: Fazli
authors.initials: F
authors.lastname: Wahid
authors.forename: Hyuk
authors.initials: H
authors.lastname: Jung
authors.forename: Taous
authors.initials: T
authors.lastname: Khan
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Hwang
authors.forename: Jong Seok
authors.initials: JS
authors.lastname: Park
authors.forename: Su-Chan
authors.initials: SC
authors.lastname: Chang
authors.forename: Mir Azam
authors.initials: MA
authors.lastname: Khan
authors.forename: You Young
authors.initials: YY
authors.lastname: Kim
mesh_terms: D000818:Animals; D004596:Electroretinography; D018756:GABA Antagonists / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D011892:Rana catesbeiana / Q000502:physiology*; D027824:Rosaceae / Q000737:chemistry*; D014785:Vision, Ocular / Q000187:drug effects*
chemical_list: D018756:GABA Antagonists; D010936:Plant Extracts