Dark adaptation of human rod bipolar cells measured from the b-wave of the scotopic electroretinogram.

摘要: To examine the dark adaptation of human rod bipolar cells in vivo, we recorded ganzfeld ERGs to (a) a family flashes increasing intensity, (b) dim test presented on range background intensities, and (c) before, up 40 min after, exposure intense illumination eliciting bleaches from few per cent near total. The flash ERG was characterized by prominent b-wave response generated principally cells. In presence reached peak earlier desensitized according Weber's Law. Following bleaching exposures, initially greatly desensitized, but thereafter recovered slowly with time. For small bleaches, desensitization accompanied acceleration, much same way as for real light. near-total bleach, unrecordable >10 min, after ∼23 half-maximal sensitivity reached, full restored between ∼35 min. With smaller recovery commenced earlier. We converted post-bleach measurements into ‘equivalent intensities’ using Crawford transformation. Across levels, results were described ‘S2’ component (0.24 decades min−1) together slower ‘S3’ (0.06 min−1), is found scotopic visual system. attribute S2 unregenerated opsin, speculate that S3 ion channel closure all-trans retinal.