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Why Do Corticosteroids Increase the ERG Amplitude? an Experimental Study in Rabbits

  • Akira Negi
  • Yoshihito Honda
  • Shin-Ichiro Kawano
Part of the Documenta Ophthalmologica Proceeding Series book series (DOPS, volume 23)

Abstract

Effects of betamethasone and dexamethasone (which have no mineralocorticoid action) on the visual function of adult albino rabbits were studied in in vitro and in vivo. In in vitro study, betamethasone and dexamethasone had no effects on ERG at a concentration of 4x 10-5 g/ml or below. Concentration of 8x 10-5 g/ml increases the amplitudes of in vitro ERGs, but the concentration was considered too high to be a possible level in vivo. An intravenous injection (single shot) of betamethasone 0.5 mg/kg body weight did not change ERGs and VECPs within 5 hours observations. In chronic in vivo study (daily intravenous injections of betamethasone 0.1 mg/kg and 0.3 mg/kg body weight for 15 days), ERGs did not change so much.

Based on these observations, we concluded that glucocorticoids have no direct effect on the visual functions of rabbits, and that the increase of ERG amplitude previously reported might be secondary to any environmental change.

Keywords

Visual Function Single Shot Implicit Time Mammalian Retina Cotton Wick 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Dr W. Junk by Publishers 1980

Authors and Affiliations

  • Akira Negi
    • 1
    • 2
  • Yoshihito Honda
    • 1
  • Shin-Ichiro Kawano
    • 1
  1. 1.Department of Ophthalmology Faculty of MedicineKyoto UniversityJapan
  2. 2.KyotoJapan

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