[Scanning electron microscopic study of the development of crystalline lens fiber]

To elucidate the 3-dimensional structural development of the albino rabbit lens fiber, and to study how cataracts affect these fibers, the lenses from rabbits 1, 2, 4, and 8 weeks old, and from 8 week old rabbits with cataracts caused by naphthalene were examined with a scanning electron microscope. The results were: 1) Normal rabbit: The ratio of the length of the anterior suture line to the diameter of the lens gradually rose from 1 to 4 weeks and then reached a plateau. The ratio of the length of the posterior suture line was constant from the first week on. Fibers were wider in lenses from older rabbits, except for those in the middle of the suture line. Ball-and-socket junctions were common on the anterior side and were concentrated in the area of the paraanterior suture line of lenses from older animals. The lateral large processes were only noted near the anterior suture line, and in extended direction from its end. The likelihood of finding edge processes, especially in the area of middle anterior and posterior sections, rose with age. 2) Rabbit exposed to Naphthalene: The rate of increase of the length of the anterior suture line and the diameter of the lens were both low, but their ratio did not differ from that of a normal rabbit's lens. On the contrary, the growth rate of the posterior suture line was much greater than that of the diameter. The peculiarity of distribution of edge processes and width found in normal lens fibers was not found in naphthalene-affected fibers.