RHO and retinal degeneration: These animals include (1) retinal degeneration (rd) mice; (2) retinal degeneration slow (rds) mice; (3) transgenic mice carrying P347S and Q344ter mutations in the rhodopsin gene; (4) knockout mice deficient for the b2-subunit of Na1/K1-ATPase expressed in retinal Müller cells; and (5) Royal College of Surgeons (RCS) rats, in which photoreceptors were detected that diedvia the apoptotic pathway as evidenced by histological morphology, TUNEL (terminal deoxynucleotidyl transferase-mediated biotin-dUTP nick end-labeling) assays, and/or by retinal DNA laddering with gel electrophoresis.