Development of ganglion cell topography in ferret retina

The adult ferret has approximately 90,000 retinal ganglion cells, arranged in a prominent area centralis and visual streak. The role of differential cell generation, cell death, and retinal growth in the control of adult retinal ganglion cell number and distribution was evaluated by examining basic aspects of retinogenesis, including growth in retinal area, develop-mental changes in the number, size, and distribution of ret-inal ganglion cells (identification aided by retrograde trans-port of HRP), and the incidence of degenerating cells in the ganglion cell layer. Retinal development in the ferret was also compared to retinal development in the cat (which has an even more differentiated area centralis) to determine what alterations of developmental parameters are most closely associated with this species difference in adult morphology. The area of the retina increases linearly from birth (1