Renewal of rod outer segments following light-induced damage of the retina.
Fluorescent lighting was used to induce severe but reversible damage of the rod outer segments of the retinas of albino rats. The animals were then kept in continuous darkness for up to 12 days. Pairs of animals were killed after 1, 3, 5, 7, 9 and 12 days of continuous darkness. Light microscopic examination of the retinas demonstrated a sharp demarcation between the light-damaged distal ends of the rod outer segments and the newly formed proximal ends. Measurement of the proximal ends demonstrated proximo-distal renewal of the rod outer segments during the first 9 days of continuous darkness. Parametric statistical analysis of the data revealed that the renewal occurred linearly, at an average rate of 2.66 micron/d, which is similar to the rate of renewal of the rod outer segments in the undamaged retina of the rat.
D000818:Animals; D003623:Dark Adaptation; D008027:Light / Q000009:adverse effects*; D010786:Photoreceptor Cells / Q000502:physiology* / Q000528:radiation effects; D051381:Rats; D012038:Regeneration